Heathrow needs a new runway, says Gordon Brown
A High Court defeat will not change the government's plans to build a third runway at Heathrow, ministers say.
Protest groups said the government's policy was "in tatters" after a judge ordered the plans to be reconsidered.
But Gordon Brown said a new runway was still the "right" decision to help economic recovery and had been reached after detailed consultation.
The Conservatives and Lib Dems have both said they would scrap the third runway if they win the election.
Lord Justice Carnwath, sitting in the High Court London, upheld campaigners' argument that the government's policy support for a third runway will need to be looked at again.
The decision does not rule out a new runway but calls for a review "of all the relevant policy issues, including the impact of climate change policy".
But speaking at a press conference in Brussels, Gordon Brown said Heathrow was "vital not just to our national economy, but enables millions of citizens to keep in touch with their friends and families".
Mr Brown insisted the government had backed an extra runway "only after a detailed assessment showing that the strict environmental limits for expansion could be met".
He added: "We are taking seriously both the concerns that people have and the need for public consultation.
"But we took a tough decision, the right decision necessary for the future of Britain and the economy, and a new runway will help secure Britain's economic future."
Shadow transport secretary Theresa Villiers said the High Court ruling meant "Labour's flagship transport policy is in complete disarray".
"This judgement is a damning indictment of Labour's wholly misguided support for a third runway."
But Transport Secretary Lord Adonis accused the Conservatives of "opportunism", arguing that they too backed more runways in south-east England, just not at Heathrow.
He said the High Court ruling had not killed off plans for a third runway, just ordered more consultation, something he said the government would do.
He told BBC Radio 4's The World at One: "What the judge did this morning was refuse to quash the government's decision.
"He said he would not quash this decision and he also said that a complete legal framework was in place for the further consultations in respect of Heathrow which the Government has always said we were going to conduct."
And the transport secretary insisted: "The process that was in place before this judgement is exactly the same process as will take place after this judgement.
"Today's judgement marks no change whatsoever in the policy on Heathrow."