The first runway will be built at the relatively under-used Stansted airport northeast of the capital by 2011 or 2012, the Department of Transport said in a major policy document about the future of British airports.

Heathrow airport, Europe's busiest air hub, west of London, will receive another runway and extra terminal capacity by 2015-20, "but only if stringent environmental limits can be met", the document said.

However more ambitious plans to relieve congestion by building a completely new airport servicing London at Cliffe in Kent, directly east of the city, had been rejected, Transport Secretary Alastair Darling told parliament.

The option of building another new facility in central England was also not necessary, he said.

But urgent action was needed, Darling said, unveiling the plan which is designed to guide the next 30 years of airport policy.

"There has been a five-fold increase in air travel since the 1970s," he said in a statement accompanying the document.

"Half the population now flies at least once a year, and many fly far more often than that. Forecasts suggest demand could be two-and-a-half times current levels by 2030."

Air travel was "essential" to the British economy, employing 200,000 people directly and 600,000 indirectly, the minister said.

But his plans were immediately condemned by environmental and anti-noise groups as irresponsible.

Friends of the Earth, which argues that the expansion of air travel worsens problems such as global warming due to pollution from planes, said the government had "sacrificed its environmental responsibilities to satisfy the demands of the aviation industry".

Airlines welcomed the news. British Airways, which is based at Heathrow, said it "congratulated" ministers on agreeing in principle to expand the airport.

"For the first time, we have an effective forward-looking aviation policy which recognises Heathrow's key role as Britain's main gateway airport," said BA chief executive Rod Eddington.

SPACE.WIRE