With the idea of creating a third runway at Heathrow Airport back in the news thanks to the new Labour chancellor Rachel Reeves giving a speech (in January 2025) to business leaders in which she said that an expansion would “make Britain the world’s best connected place to do business”, we decided to have a quick look back at the history of those efforts and opposition to them.
Reeves has said she wants to get a planning application for the third runway “signed off” before the next election (in around 2029). Time will tell if that proves possible.
Early Plans and Initial Approval (2000s)
Serious talks of expanding Heathrow Airport with a third runway began in the early 2000s. A 2003 aviation white paper under the Labour government signaled support for a new runway, and by November 2007 officials launched public consultations on a proposed third runway and sixth terminal.
In January 2009, Transport Secretary Geoff Hoon formally announced the government’s backing to build a 2,200 m third runway alongside a new terminal, aiming for it to be operational by around 2015 . This plan, supported by business groups and trade unions, would require demolishing about 700 homes (with compensation offered) and limiting initial additional flights to 125,000 per year (capped below full capacity for environmental reasons) .
Despite government support, opposition was fierce from the start. The Conservative and Liberal Democrat parties (then in opposition) vehemently opposed Heathrow expansion, aligning with local residents, environmental campaigners, and figures like London’s Mayor Boris Johnson .
By 2002, villagers near Heathrow had formed the No Third Runway Action Group (NoTRAG) to fight the plans . Environmental groups also launched high-profile campaigns – notably Greenpeace, which in early 2009 bought a plot of land directly on the proposed runway site (in the village of Sipson) and subdivided it among thousands of co-owners (including celebrities) to complicate compulsory purchase .
As Greenpeace’s director explained, “as the new owners of the land… we’ll resist all attempts at compulsory purchase” to stop the runway . Such creative protests captured public attention, as did a “Climate Camp” at Heathrow in 2007 and other stunts. The Conservative leader David Cameron capitalized on the momentum, famously pledging ahead of the 2010 election: “No ifs, no buts, there will be no third runway” .
Political Reversal and Cancellation (2010)
In May 2010, this political opposition translated into action. The newly elected Conservative–Liberal Democrat coalition government honored its promise and canceled Heathrow’s third runway plan as part of the coalition agreement .
Airport owner BAA (now Heathrow Airport Holdings) formally withdrew its application weeks later . This was a triumphant moment for campaigners – local residents and groups like NoTRAG had, against the odds, helped halt a £9 billion expansion. The victory, however, came with caution: residents knew the issue could resurface, so they kept campaign networks alive in “mothballed” form .
Indeed, business lobbyists (e.g. London First) immediately began urging the government to rethink the decision , arguing that Heathrow’s congestion was a growing problem. The third runway saga was far from over.
Revival via Airports Commission (2012–2016)
By 2012, pressure was mounting over airport capacity in southeast England. The government, still wary of a political backlash if it U-turned too quickly, set up the independent Airports Commission chaired by Sir Howard Davies to review options for expansion.
After three years of study, in July 2015 the Airports Commission delivered its final report, unequivocally recommending a new northwest runway at Heathrow as the best solution to increase capacity and connectivity . The Commission projected that adding a third runway (along with another terminal) would allow Heathrow to handle up to 740,000 flights per year once completed.
This put the expansion back on the political agenda, albeit with conditions related to noise and air pollution. Conservative Prime Minister David Cameron had previously vowed to block the runway, and facing the upcoming 2016 London mayoral race (in which Heathrow expansion was a hot issue), he delayed any decision on the report . Ultimately, Cameron left office without acting on it.
In October 2016, his successor Theresa May’s government took the politically delicate step of reviving the Heathrow expansion.
On 25 October 2016, the government officially endorsed the third runway plan as national policy, subject to detailed consultation and regulatory approval . Essentially, May’s cabinet gave Heathrow expansion the green light, reversing the 2010 cancellation. This decision, coming from a Conservative government that once opposed the runway, marked a significant political shift.
It triggered the reactivation of anti-runway campaigns: in 2017, a broad coalition of environmental and community groups formed the No Third Runway Coalition to unite opposition across London and beyond. Long-time opponents like John McDonnell (the local MP) and Boris Johnson (now Foreign Secretary, who once quipped he’d “lie down… in front of those bulldozers” to stop the runway) remained vocal, even as the project inched forward.
Heathrow Airport Ltd, for its part, began drawing up detailed masterplans and cost-cutting measures (proposing to drop a new terminal to save £2.5 billion) in preparation for the lengthy planning process .
Parliamentary Backing and Mounting Opposition (2018)
After consultations, the government put the National Policy Statement (NPS) on Airports, which included Heathrow’s third runway, to Parliament. In a key vote on 25 June 2018, the House of Commons overwhelmingly approved the third runway NPS by 415 votes to 119.
This cross-party majority gave the expansion an official parliamentary mandate. However, the vote also revealed divisions: dozens of MPs representing London constituencies broke ranks to oppose or abstain, citing the impact on their communities . Notably, then-Labour leader Jeremy Corbyn and a young backbencher named Keir Starmer voted against, while many other Labour MPs (and the Conservative frontbench) voted in favour, showing how the issue cut across usual party lines.
Outside Westminster, the vote was met with immediate resistance. A group of London local authorities (Hillingdon, Wandsworth, Richmond, and Hammersmith & Fulham), together with the Mayor of London Sadiq Khan and organizations like Greenpeace and Friends of the Earth, filed for judicial review to challenge the legality of the government’s decision. “We will hold the Government to account on their climate obligations,” Sadiq Khan vowed, as he prepared to fight the plan in court .
Meanwhile, environmental activists staged bold protests to dramatize their opposition. In the hours before the June 2018 Commons vote, demonstrators from “Vote No Heathrow” even staged a sit-in protest inside Parliament – lying down in the Westminster central lobby and chanting to disrupt MPs on their way to vote . This “lie-in” referenced Boris Johnson’s bulldozer promise and briefly put the Parliament in lockdown.
A few years prior, in July 2015, direct-action group Plane Stupid had similarly grabbed headlines when a dozen activists cut through Heathrow’s perimeter fence and chained themselves together on the north runway, halting flights for hours . “Building more runways goes against everything we’re being told by scientists…that’s why we’re here,” one Plane Stupid protester explained, apologising to disrupted travellers but insisting that aviation growth would wreak climate havoc . These dramatic protests underscored the depth of grassroots opposition to Heathrow expansion – from local village residents in Harmondsworth, to climate campaigners willing to face arrest. By late 2018, the battle lines were drawn: Heathrow and its business allies had political approval to proceed, but opponents were taking the fight to the courts and the streets.
Legal Battles and Climate Campaigns (2019–2020)
The next phase of the saga unfolded in the courts. In early 2019, multiple lawsuits against the Airports NPS (and Heathrow expansion within it) were heard jointly – claimants included several London boroughs, environmental NGOs (Friends of the Earth, Plan B, Greenpeace), and even a rival Heathrow Hub proposal objecting on different grounds.
In May 2019, the High Court (Divisional Court) delivered a blow to opponents by dismissing all claims against the third runway approval . The judges found the government’s process lawful on all 26 grounds of challenge, rejecting arguments about air quality, noise, climate, and other issues. Undeterred, the coalition of campaigners immediately appealed, zeroing in on one especially significant argument: that the government had failed to account for its international climate change commitments. In particular, Friends of the Earth and Plan B argued that the Paris Agreement (ratified by the UK in 2016) and the looming climate impacts of aviation had been unlawfully ignored when the policy was set .
In a landmark ruling on 27 February 2020, the Court of Appeal stunned Heathrow by siding with the climate campaigners. It declared the government’s approval of the third runway “illegal” on climate change grounds, halting the project . The court found that the transport secretary had failed to consider the UK’s climate commitments under Paris and the full long-term emissions impact of the expansion .
This victory — the first time a major infrastructure project was overturned due to the Paris climate accord — was hailed as “historic” by Friends of the Earth . Judges made clear that the ruling didn’t permanently kill the runway, but the government would need to review its policy to align with climate duties. The timing was powerful: the decision came amid growing public focus on the “climate emergency,” essentially vindicating years of climate campaigning. It “stops the climate-wrecking plan dead in its tracks,” Friends of the Earth declared, calling the win a vital step in holding the government accountable to its environmental pledges . Following the judgment, the Conservative government (under PM Boris Johnson, a longtime runway skeptic) announced it would accept the court’s decision and not appeal . Many assumed the project might quietly fade away.
However, Heathrow Airport Ltd was not ready to give up. Arguing that the Court of Appeal had erred, Heathrow appealed to the UK Supreme Court. In December 2020, the legal pendulum swung back. The Supreme Court unanimously overturned the February ruling, reviving the runway plan . The top court decided that the government’s initial policy had sufficiently accounted for climate factors as required at the time. Specifically, it held that ministers had some discretion in how to consider international climate agreements, and that the Paris Agreement – while important – did not yet legally bind UK infrastructure policy when the Airports NPS was drafted.
This ruling re-legitimized the expansion and cleared the path for Heathrow to seek planning permission. “The project can now seek planning permission, but ultimate completion…remains uncertain,” noted analysis of the verdict, which called it the latest twist in a years-long political and legal wrangle . Indeed, the Supreme Court emphasized that full climate and environmental scrutiny would come at the planning stage, where Heathrow would have to make its case in detail. Friends of the Earth vowed to continue the fight during that planning process, stressing that the judgment was “no ‘green light’” to actually start building. Nonetheless, by early 2021 the legal roadblock had been lifted – Heathrow’s third runway was once again legally permissible, pending future planning approvals.
Pandemic Fallout and Project Pause (2020–2023)
Even as the Supreme Court cleared the runway on paper, real-world events threw the project into doubt.
The COVID-19 pandemic that struck in 2020 led to an unprecedented collapse in air travel. Heathrow – normally Europe’s busiest airport – saw passenger numbers and airline revenues plummet. The airport’s management and airlines alike were forced into survival mode, postponing long-term expansion plans. By 2021, Heathrow’s chief executive noted that the third runway would be delayed by at least a few years, if it happened at all, given the financial hit and uncertain recovery of demand.
In effect, the project entered a holding pattern. In 2022 and 2023, as aviation began to rebound, Heathrow’s capacity constraints and crowding issues returned, but so did questions about the huge cost (estimates of £14–18 billion) of a new runway in a changed economic climate. Investors were cautious, and the government had other priorities amid the pandemic recovery. Heathrow’s expansion was described as “stalled” – still officially on the books, but not actively moving forward .
By mid-2023, industry analysts noted the plan was “far from certain” and possibly on ice until better times . Importantly, in this period the UK adopted more stringent climate targets (aiming for net-zero emissions by 2050) and the Climate Change Committee warned that any airport growth must be balanced by cuts elsewhere to meet carbon budgets.
The political narrative began to shift: talk of “building back greener” after COVID made a new runway even more controversial. Indeed, by late 2023, many assumed the third runway might quietly be shelved for good – a victim of both climate imperatives and the pandemic’s economic shock. Yet, as it turned out, the idea was merely awaiting a change in political winds.
New Labour Government Renews the Push (2024–2025)
In late 2024, a general election brought a new Labour government to power in the UK, and with it a renewed drive to revisit big infrastructure projects. To the surprise of some, Prime Minister Keir Starmer’s administration quickly put Heathrow’s third runway back on the agenda.
In January 2025, Chancellor of the Exchequer Rachel Reeves confirmed that proceeding with the third runway was official government policy once again – this time under Labour leadership . Speaking in Oxfordshire, Reeves outlined an ambitious economic plan and explicitly included the Heathrow expansion as a centerpiece. “We cannot duck the decision any longer,” she declared, calling the runway “badly needed” after decades of constrained growth at Heathrow . The government signaled it would streamline the approval process (“cut the red tape”) and aimed to get construction started within the current parliamentary term . Reeves even suggested she wanted “spades in the ground” before the next election, with a goal of the runway opening by around 2035.
This renewed push represents a dramatic policy shift for Labour, which had largely opposed the runway when out of power (Starmer himself voted against it in 2018). Several factors explain the change. Economically, the government argues that extra airport capacity is vital for post-Brexit Britain: Heathrow is effectively full at about 480,000 flights per year, and demand has nowhere to grow .
Adding a third runway could increase capacity to 700,000+ flights, allowing many new routes and more reliable operations. Reeves noted that backing a third runway would “make Britain the world’s best-connected place to do business” . Heathrow currently handles 60% of the UK’s air freight and £200 billion in trade annually; with expansion, it could handle even more . The Labour government is also positioning the project as part of a broader pro-growth agenda, alongside new railways, housing, and green industry investments .
Politically, embracing the runway helps Labour court business groups and trade unions (many of which have backed the project for the jobs and investment it promises ). It also allows Labour to draw a contrast with the previous Conservative government, which despite approving the runway in theory, never actually delivered it. Now in charge, Labour appears keen to show it can take decisive action on infrastructure after years of indecision.
That’s not to say the controversy has gone away. The announcement immediately exposed divisions within Labour’s own ranks. Senior figures with green credentials, like Environment Secretary Ed Miliband, cautioned that any airport expansion must strictly meet Britain’s emissions targets – or “it won’t go ahead” if it can’t . Miliband (a longtime opponent of the third runway since 2009) reassured that the government would hold the project to carbon budget tests, implicitly warning Heathrow that failure to hit climate safeguards could still scuttle it .
London’s Mayor Sadiq Khan likewise blasted the new push, reiterating his “strong opposition” due to the “severe impact” on noise, air quality, and climate goals for Londoners . He and several environmental groups pledged to scrutinize any new plans and potentially relaunch campaigns against the runway .
Even within the Cabinet, Prime Minister Starmer is known to have past reservations, whereas Chancellor Reeves has been a consistent supporter (she notably voted in favour in 2018) . Still, the official government line is united in moving forward. Reeves insisted the project will be delivered “in line with our legal environmental and climate objectives” , suggesting measures will be taken to mitigate emissions and pollution. With political will restored at the top, Heathrow’s owner has dusted off its plans: the airport’s CEO thanked the government for its “bold, responsible vision” and signaled Heathrow will accelerate work to update its proposal for approval .
Why is the Third Runway Back on the Agenda?
The Labour government’s renewed push for Heathrow’s third runway in 2025 stems from a combination of economic, political, and infrastructural factors:
• Economic Recovery and Growth: After a decade of sluggish growth – exacerbated by Brexit and the pandemic – the UK is eager to stimulate its economy. Expanding Heathrow is pitched as a “runway to growth,” expected to create tens of thousands of jobs and inject billions into the economy. The airport acts as a critical trade gateway; more capacity means more flights for business travelers and tourists, and greater volume for high-value air cargo. By adding new long-haul routes to emerging markets, Britain can “open new export markets” and attract investment . In short, the third runway is seen as an infrastructure project that could help “speed up the country’s sluggish economy” – a priority for the new government. Chancellor Reeves has framed the decision as ending years of indecision that may have signaled a lack of ambition to global investors . Her message: Britain is now decisively “open for business” and willing to build big.
• Heathrow’s Capacity and Global Competition: Heathrow has only two runways and has been operating at roughly 98% of its permitted capacity for years, handling about 480,000 flights annually . This choke point limits the UK’s connectivity. In contrast, rival European hub airports like Paris Charles de Gaulle, Amsterdam Schiphol, and Frankfurt each have four or more runways and room to grow. Airlines have warned that without expansion, London will continue to lose potential routes to these competitors. For example, important connections to regional Chinese or South American cities might choose Paris or Amsterdam if Heathrow slots are unavailable. The new runway would allow up to ~700,000 flights per year, easing delays and enabling Heathrow to regain a competitive edge . The airport already carries a huge proportion of UK trade and visitors; expansion would solidify its status as a global hub into the 21st century. Infrastructurally, the Labour government views this as catching up on overdue development – Britain’s first full-length runway in the southeast since World War II. Additionally, with HS2 rail and other transport links under construction, there is an opportunity to integrate Heathrow’s expansion with better ground transport, spreading the benefits nationwide.
• Political Signaling and National Strategy: Embracing Heathrow expansion also has a political calculus. Labour under Starmer wants to shed any past image of being “anti-business” or economically cautious. Backing a major infrastructure investment shows a pro-growth, can-do attitude that appeals to business leaders (the CBI and Chambers of Commerce have long lobbied for the runway) . It also aligns Labour with many in the working class who welcome the promise of construction and airport jobs. Furthermore, the decision fits into a broader national strategy to “level up” and modernize infrastructure. After years of contentious debate, pushing the runway now allows Labour to claim it is resolving a long-running issue in the national interest. Politically, there is also cross-party cover – since many Conservatives had supported the runway – making it a relatively safe bet despite some internal dissent. By moving early in its term, the government likely hopes to have the controversy settled (and the project well underway) by the next election.
• Managing Climate and Local Concerns: The government argues that it can pursue the third runway without betraying its climate commitments. Technological and regulatory developments are cited in support: more efficient aircraft, sustainable aviation fuels, and the possibility of capping emissions through carbon trading or offset schemes. Reeves and her colleagues have stressed that the project must align with “legal…climate objectives” and have promised a thorough environmental assessment as part of updating the Airports NPS . Essentially, they contend it’s possible to have an expanded Heathrow and meet net-zero by 2050, if the aviation sector innovates and if emissions growth at Heathrow is balanced by reductions elsewhere . Nevertheless, this remains the thorniest aspect of the plan. To placate critics, the government may impose conditions such as limits on noise, air pollution mitigation, and requirements that the airport and airlines make investments in greener technology. The local impacts – loss of homes in villages like Harmondsworth and increased noise for West London – are also acknowledged challenges . Labour’s renewed push comes with assurances of community engagement and improvements to public transport access for the airport. These measures are meant to blunt opposition, though many campaigners remain unconvinced.
In summary, the third runway project has navigated a decades-long flight path through shifting political skies: from early Labour backing, to Conservative cancellation, to revival and court battles, and now an unexpected second wind under a new Labour government. Each chapter has been marked by pitched battles between economic and connectivity ambitions on one side, and environmental and community protections on the other. Key moments – from Cameron’s “no ifs, no buts” promise , to Plane Stupid activists on the tarmac , to the Court of Appeal’s climate verdict in 2020 – have all shaped the trajectory of this contentious project. As of 2025, with political momentum restored, Heathrow’s third runway is back in motion. Yet, given its turbulent history, few would be surprised if further twists and turns await. The coming years will determine whether this long-debated runway finally takes off, or whether opposition forces once again force it back to the gate.
Sources: Historical timeline and government decisions; Environmental campaigns and opposition ; Court rulings and legal battles; Recent political shifts and Labour’s stance .