Foreign Secretary William Hague has ruled out a change of Government policy on a third runway at Heathrow, as reports emerged of plans for a new four-runway airport which could be submitted as a solution to the aviation capacity crisis.
Speaking to Sky News' Dermott Murnaghan, Mr Hague said the Government did not intend to break its election promise about not building a third runway.
"That's not something that this Government, this Coalition, will be doing," he said.
"It's important to make the right decision about this and study all the options.
"We said very specifically we would not be (building a third runway). Because a runway or an airport takes such a long time, this does not have an immediate effect on the economic situation now and our airport capacity now, but there are others things which do have an effect."
Mr Hague’s comments came after The Independent on Sunday revealed that a world-leading infrastructure firm is assessing potential sites to the west and north-west of London.
They are understood to include possible sites in Oxfordshire and Berkshire.
With an estimated cost of between £40bn and £60bn, the proposed "London West" airport would need to be located within 30 minutes' travel of the capital, according to a briefing document seen by the newspaper.
That would likely place it on the Great Western mainline, which runs from London to Maidenhead, or on the High Speed Two rail link between the capital and Birmingham.
The Coalition is at odds over how to solve the current capacity crisis at airports in the South East and proposals for a third runway at Heathrow or a Thames Estuary airport - backed by London Mayor Boris Johnson - have caused controversy.
In July, consultation on aviation capacity was delayed for a second time over claims the Conservatives were now considering another runway at Heathrow.
The Liberal Democrats are expected to restate their opposition to airport expansion later this month at the party's annual conference in Brighton.
And in June, Birmingham Airport launched an advertising campaign marketing itself as an alternative international hub to the major London airports.
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