Campaigners trying to block Heathrow expansion have lost a High Court challenge against controversial plans for a third runway.

A group of councils, residents, environmental charities and Mayor of London Sadiq Khan brought four separate judicial reviews of the Government’s decision to approve the plans.

During a two-week hearing in March, they argued the plans would effectively create a “new airport” with the capacity of Gatwick and have “severe” consequences for Londoners.

But their cases were dismissed by two leading judges on Wednesday.

Lord Justice Hickinbottom, sitting with Mr Justice Holgate, said in the ruling: “We understand that these claims involve underlying issues upon which the parties – and indeed many members of the public – hold strong and sincere views.

“There was a tendency for the substance of the parties’ positions to take more of a centre stage than perhaps it should have done, in a hearing that was only concerned with the legality, and not the merits, of the Airports National Policy Statement.”

The case was brought against Transport Secretary Chris Grayling by local authorities and residents in London affected by the expansion, and charities including Greenpeace, Friends Of The Earth and Plan B.

The campaigners claimed the Government’s National Policy Statement (NPS) setting out its support for the project failed to properly deal with the impact on air quality, climate change, noise and congestion.

Support from Labour MPs helped push through the proposals to expand Europe’s busiest airport with an overwhelming majority of 296 in a Commons vote in June last year.

Mr Grayling said at the time that the new runway would set a “clear path to our future as a global nation in the post-Brexit world”.

Construction could begin in 2021, with the third runway operational by 2026.