Andy Burnham said he is “reticent” to say whether or not he supports a third runway at Heathrow because there are “strong views on either side”, despite ministers backing the scheme because of its economic potential.

The Prime Minister said there was “some way to go” before a final decision on expanding the UK’s busiest airport.

But a series of ministers have said the scheme is important for boosting trade with countries around the world and securing British jobs.

Mr Burnham told LBC Radio he acknowledged it was “not just a matter for London”, having said yesterday it was “principally” an issue for the capital.

Despite other ministers having thrown their weight behind the plan, Mr Burnham insisted he could not prejudice any potential planning decision.

The Prime Minister said: “It is a big decision. The reason why sometimes politicians do have to do this ‘oh, I can’t give you a straight answer’ is it’s a live consultation and potentially planning application, which takes it into a different space because those issues will have to be looked at carefully.

“And the reason why I am a little reticent is because there are quite strong views on either side. There’s a very significant difference of opinion on the whole matter.

“So people need to have the sense that these issues are going to be looked at independently, fairly, and obviously that’s something that I need to respect in making my comments on the situation.”

But at the Labour Party conference, Business Secretary Jonathan Reynolds said there was a “trade argument” for expansion because of the growth of cities, particularly in Asia, which currently had no direct link to the UK.

“We will need a global top-tier airport,” he told a conference fringe event.

He acknowledged local concerns around the airport, but added: “If you asked in Scotland or MPs in the North East they know there is a relationship between Heathrow and their regional economic output because obviously Heathrow is the biggest (freight) port as well as passenger traffic.”

And Treasury minister James Murray told the Press Association a third runway will make the UK “stronger”.

Mr Murray, whose Ealing North seat is in west London, said it was not just an issue for the capital but affected the whole country.

He said: “What the Prime Minister set out yesterday was that it’s important to listen to Londoners and I know that – I’m a London MP and if I listen to my constituents, you know there are different views on it.

“But I think we recognise that having that third runway is really important for jobs, it’s really important to get that investment into Heathrow and it’s actually really important for the whole country because that investment in making Heathrow stronger, making our country stronger, making sure that we boost trade and making sure we get more jobs right across the country is really important for our future.”

Asked why the Prime Minister could not give his full backing to the project, Mr Murray said: “Well, he was saying that it’s important to listen to what Londoners have to say and there’s been a consultation.

“The Government’s now looking at the consultation responses and will set out its response shortly.”

He added: “I think Heathrow has a really important role to play and as an MP in west London, I know how important it is for jobs and my constituents.

“But it’s not just an issue for my constituents or for people in west London or even that region.

“It’s for the whole country and it’s really important to have investment in aviation right across the country. And Heathrow is a critical part of that.”

Labour’s support for the third runway was set out by former chancellor Rachel Reeves in January 2025.

Estimated to cost £33 billion, including £1.5 billion to move the M25 to build the runway, the scheme is expected to be fully privately financed.

It would see Heathrow’s capacity increase to 756,000 flights and 150 million passengers per year

Ms Reeves had suggested the runway could be open in 2035, but airport bosses have told ministers that timetable appears impossible to meet.

The airport aims to get planning permission by 2029, and from that point believes building the new runway within a decade to be a reasonable goal.

Mr Reynolds said: “We should do big infrastructure faster in the UK than we do.”