Chancellor George Osborne’s Budget speech admission over the negative impact to the UK of scarce London-area airport capacity is seen as a “carefully choreographed” shift in government policy.

The claim came from Abta head of public affairs Luke Pollard as Osborne made it clear the coalition’s aviation policy review was being delayed.

Osborne told MPs that the UK had to confront the “lack of airport capacity in the southeast”.

He added: “We cannot cut ourselves off from the fastest-growing cities in the world and the transport secretary will set out the government’s thinking later this summer.”

The Department for Transport originally planned to publish its review of aviation policy this month. Building a third runway at Heathrow was ruled out immediately after the 2010 election on environmental grounds.

And Osborne’s comments gave rise to speculation that the government is now taking interest in calls for a new London hub airport in the Thames Estuary.

This came as the government was attacked from all sides of the travel, airline and airport sector for failing to ditch further rises in Air Passenger Duty in the Budget.

Pollard said: “Although APD didn’t warrant an oral mention, the urgent need to address the lack of aviation capacity in the southeast of England did.

“This is encouraging and is part of a carefully choreographed policy change on aviation by the Government.

“From Mr Osborne’s comment it looks like we will have to wait until summer and not next week as many were expecting details of the government’s new aviation policy – but this mention is encouraging and shows the government realises its outright ban on new capacity was a mistake.”

Virgin Atlantic chief executive Steve Ridgway said: "We look forward to an urgent and open debate with government on all options, which must include Heathrow."

The DfT admitted that the outlines of a new policy would take a year to emerge.

"We remain committed to having a final policy in place by next spring at the latest, but we have taken the decision to wait until both documents are ready and intend to publish them in the summer," a spokesman said.