Impact on air quality a major factor in expansion plans
The impact on air quality will be a "major consideration" when the Government makes a decision on airport expansion, according to Transport Secretary Patrick McLoughlin.
He insisted that the issue was being taken "incredibly importantly" by ministers.
Building a third runway at Heathrow was recommended in July by the Airports Commission, which rejected expansion of Gatwick.
But Gatwick's chief executive, Stewart Wingate, claimed expansion of the West Sussex airport would deliver the economic boost of increased capacity "at a fraction of the environmental impact" of Heathrow.
He went on: "Heathrow's poor air quality already breaches legal limits and it is difficult to see how expansion could legally go ahead with the millions of extra car journeys an expanded Heathrow would generate.
"In stark contrast, Gatwick is well within legal air quality limits and can guarantee we would remain so with a second runway."
Mr McLoughlin said: "We take climate and we take air quality incredibly importantly, so it will be a major consideration in the decisions we make."
Sir Howard Davies, chairman of the Airports Commission, wrote to the Transport Secretary last month to state that "appropriate measures" can be taken to address air quality at an expanded Heathrow and claimed "limited weight" should be placed on the suggestion that the issue "represents a significant obstacle". Heathrow this week stepped up its campaign in Northern Ireland for support for a third runway, claiming that up to 3,400 new manufacturing jobs would be created here if the airport is allowed to grow.
It quotes research by the consultancy firm Quod, estimating that almost 95,000 manufacturing jobs would be created across the UK, with Northern Ireland getting a share.