Rachel Reeves’ public show of support for expanding Heathrow has exposed a divide within Labour ranks, with Sadiq Khan among high-profile names voicing their opposition to the plan.
Khan vowed to block any attempt to expand Heathrow, telling LBC’s Andrew Marr on Thursday that building a third runway at Heathrow would put Londoners at risk from increased air and noise pollution, and could throw the government’s climate targets into doubt.
Energy Secretary Ed Miliband has previously said he would only support expanding Heathrow if it fit with net zero targets.
And Dale Vince, a major Labour donor and green energy entrepreneur, told LBC that he hoped the plans failed.
Meanwhile the head of a major airline took aim at the plan and pointed out it could be 15 years before a third runway was operational.
The Heathrow expansion has its backers too, including Easyjet, various business groups and the GMB union.
Heathrow bosses have been trying to build a third runway for nearly 20 years amid concerns over constrained capacity at the airport, one of the world’s busiest.
Advocates say that expanding capacity will enable Britain to grow faster by attracting more visitors and investment - and believe that the failure to build a third runway is symptomatic of the UK’s aversion to creating the necessary infrastructure for growth.
The scheme would involve around seven years of construction to produce a third runway and a new terminal, and would require more than 700 houses to be demolished and the M25 motorway to be moved into a tunnel.
Reeves, the Chancellor, said on Wednesday she would support expanding the airport as she seeks to grow the economy - while also insisting that there did not need to be a trade-off between the environment and growth.
She gave her backing to the third runway plans as part of a major speech in which she announced several infrastructure projects while reaffirming her commitment to growing the UK economy.
Khan insisted that he went along with all of Labour’s plans to boost the economy by building more - other than the extra runway.
He insisted that he was "pro-growth" and "pro-business" and had been "calling out for the need for government support for growth for a long time".
Khan pointed out that it was up to Heathrow to bring plans for expansion, not the government.
He said: "Let’s wait and see the plans that Heathrow bring forward in relation to a third runway.
"The last plans they had would have meant building over the busiest motorway in the country, the M25, a tunnel underneath the M25, re-routing the A4, increasing the capacity of the Elizabeth Line, the Piccadilly Line, Southern Rail, bulldozing a village."
He said he was "somebody who takes tackling the climate emergency seriously, but also thinks a green transition is one of the greatest opportunities we have this century" - adding that he would "use any tool in the toolkit to stop a third runway happening."
"We’ve been frustrated by the hurdles there are to get permission for infrastructure. We’ve been frustrated by the difficulties in building high-quality, high-density homes around stations. We’ve been frustrated by the Golden Triangle of London, Oxford and Cambridge, not fulfilling its potential."
Meanwhile Downing Street also sought to play down the rift between Khan and the government over Heathrow.
Asked if Khan’s opposition made him a blocker, a Labour spokesperson said "No, we agree with the Mayor of London that growth must come hand-in-hand with our climate obligations, and that’s why the Chancellor set out that we support a third runway.
"That will be in line with our climate obligations and we look forward to working closely with the mayor throughout the process."
Some other Labour MPs have also voiced their opposition to Heathrow expansion plans - including John McDonnell, the former Shadow Chancellor under Jeremy Corbyn, who raised environmental concerns.
McDonnell’s west London constituency, Hayes and Harlington, is also close to Heathrow, so constituents would be affected by any increased noise.
Dale Vince, the founder of Ecotricity and a major Labour donor, said that the trade offs "just don’t make sense" and claimed that the economic gains were "marginal".
He told LBC News that improvements in video calling made business travel less viable, without giving much evidence.
Old Windsor, Berkshire, UK. 29th January, 2025. Views of London Heathrow in West London on a murky day. Picture: Alamy
But Reeves hit out at critics of the plan, telling LBC that “sustainable aviation and economic growth go hand in hand".
She added: “There have been huge changes in the way people fly in the last few years, and just this year we’ve introduced the sustainable aviation fuel mandate, which will be increasing in the years ahead.
“£63 million today into producing sustainable aviation fuel, which will encourage and help create jobs here in Britain in places like Teesside.
“We’ve said to Heathrow that we want the plans that they bring forward by the summer to meet rules around carbon emissions, noise pollution and air quality. We will work with Heathrow to make sure that those plans come forward.”
She continued: “The answer to new infrastructure can’t always be no. That’s what happened under the last government.
“And nothing got built and nothing got done and living standards deteriorated. But so it does mean having to take on people who are against new developments, whether it is wind farms, airports or new rail lines.
“And the problem is, if you always give in and say, oh, okay, there’s some objections to this, we’ll end up with a situation where the economy continues to stagnate, living standards decline, and will be no further forward than we are now.”
But the objections to the third runway are not all from an environmental perspective.
Michael O’Leary, the chief executive of budget airline Ryanair, said Reeves would deliver more growth by axing air passenger duty (APD).
He claimed that the discussion about a third runway was an irrelevancy, given that it will be over a decade before a new runway is completed.
Mr O’Leary said: "The third runway at Heathrow is a dead cat."If it ever arrives, it will be about 2040, 2045 or 2050, in fact long after I’ve departed from Ryanair.
"It will not deliver any growth. The thing that will deliver growth is abolishing APD."