Cabinet row threatens to stall airport decision

At least two senior ministers, Hilary Benn and Ed Miliband, are demanding tougher safeguards for the environment than were envisaged.

They were heading for private talks this afternoon with Transport Secretary Geoff Hoon, arguing that his blueprint for the airport's expansion be made "more green".

At the same time, Downing Street sources said the Prime Minister has agreed to an urgent meeting this week with Labour MPs opposed to the third runway. The meeting could take place tonight or tomorrow.

If the Cabinet row is settled, ministers are hoping to give a firm go-ahead on Thursday, paving the way for a huge increase in Heathrow's creaking capacity. But a delay until next week or the week after was not being ruled out by senior sources.

News of the possible delay came as a blow to Gordon Brown, who is keen to put on a united front against the threat of massive protests from anti-expansion campaign groups.

Today's weekly Cabinet meeting was expected to discuss the third runway briefly but it was clear that the final formal decision would not be ready.

Mr Benn and Mr Miliband were understood to be arguing for a range of safeguards and sweeteners to reduce pollution and make the third runway more appealing to the public.

A senior source told the Standard: "This is a really big decision and we have got to get it right."

There is no prospect of the £9 billion third runway being rejected by Labour. However, the ministerial wrangling could affect how many flights can run from it as well as how much noise and inconvenience West London residents have to put up with.