Business groups have reacted with anger to the government's delay in reaching a decision on whether to build a third runway at London's Heathrow Airport.
The British Chambers of Commerce (BCC) said it was "gutless", while another group said it would have business leaders "tearing their hair out".
They argue that the delay is bad for the UK economy.
But opponents welcomed the government's plan to wait for further environmental research before making a decision.
No decision will be made before the summer of 2016, it was announced on Thursday.
A decision had been promised previously by the end of the year.
Transport Secretary Patrick McLoughlin said the government needed to "undertake more work on environmental impacts, including air quality, noise and carbon" before deciding on how best to expand airport capacity in south-east England.
There are three options - a third runway at Heathrow, which business groups favour, a second runway at Gatwick Airport, or extending an existing runway at Heathrow.
In July, an independent report by Sir Howard Davies backed the idea of a third runway at Heathrow, but did not completely rule out the alternatives.
Heathrow Airport's chief executive John Holland-Kaye said he was confident that his airport would still be chosen.
"He [David Cameron] now accepts the need for new capacity in the South East and I am confident that he will accept the second recommendation [of the independent commission] which was that only Heathrow can deliver the jobs and growth that this country needs," he told the BBC.
The Mayor of London, Boris Johnson, who opposes Heathrow expansion, told the BBC that there was "an element of political fudge-arama" about the decision.
He added that the delay was "just inevitable" as "Heathrow is fundamentally in the wrong place".
Business groups said a decision was long overdue and questioned why the government had bothered with Sir Howard's investigation, if it did not follow his recommendation.
"Businesses will see this as a gutless move by a government that promised a clear decision on a new runway by the end of the year," said John Longworth, director general at the BCC.
"Ministers need to stop prevaricating and get on with doing what the country sorely needs," he said.
The Institute of Directors (IoD) said business leaders would be "tearing their hair out" with frustration.
The group said it now cared much less about what the decision was, and more about whether one was actually made.
"The government has set a very ambitious target of increasing UK exports to £1 trillion a year by 2020.
"If they can't fly to emerging markets to make deals, our members are going to find it very hard to meet this aspiration," said the IoD's director general Simon Walker.
The CBI said it was "deeply disappointed" and that tough decisions were needed.
Dale Keller, chief executive of the Board of Airline Representatives in the UK, said the world's airlines needed certainty to invest in the UK.
He pushed for a swift decision saying that "every week that passes has direct cost to the UK economy, its international connectivity and reputation".
Opponents of a third runway at Heathrow welcomed the plan to investigate the environmental impact further.
But they also called for an end to the uncertainty and for an outright rejection of the plan.
Green MP Caroline Lucas called for the Heathrow option to be ruled out.
Simon Clydesdale, aviation campaigner for Greenpeace UK, said: "Neither Heathrow nor the Davies Commission have managed to convince anybody that they can build a new runway without breaking pollution and carbon limits, which would be illegal - no ifs, no buts."
Conservative MP and London Mayoral candidate Zac Goldsmith, who threatened to resign if the government picked Heathrow, said the government was now in "the right place" over airport expansion and the case for expanding Heathrow was "in tatters".
The delay means no decision will be made before next year's London mayoral election, to be held on 5 May.
Mr Goldsmith's Labour opponent, Sadiq Khan, said the government had stalled in "order to avoid embarrassing their mayoral candidate".
But Patrick McLoughlin disputed that. "We have known for a very long time when the mayoral elections were going to be be, so if we deliberately wanted to say we weren't going to make this until after the mayoral elections we'd have just set the timetable for another 12 months," he told the BBC.