David Cameron has slapped down London Mayor Boris Johnson for threatening to undermine a review into the future of airports.
The Prime Minister insisted Mr Johnson was wrong to dismiss the option of a third runway at Heathrow and said he would not be given a veto on the critical issue.
"In the end the decision is a national decision that the Government has to lead," Mr Cameron told The Times. "What is not right is to say, I only want my options considered and not anyone else's."
The rebuke came after the mayor stepped up his criticism of the aviation commission headed by Sir Howard Davies, saying the plan for final decisions to be taken after 2015 was far too slow.
The inquiry should not be considering another runway at Heathrow because the idea was "a complete disaster" and "simply will not happen", he said.
Mr Johnson - who favours a new airport in the Thames Estuary - warned that the Tories would suffer if they had not ruled out the controversial move before the next general election.
However, Mr Cameron said it was right that Sir Howard went into his probe with a "completely open mind".
"What I would say to Boris, what I have said to Boris is that for the first time a government has properly put all the options, including estuary options, on the table," the premier said.
"Boris is passionate about the idea of an estuary airport. Now he has a forum in which to put forward his arguments in a way that he hasn't in the past."
Tory grandee Michael Heseltine has also stressed the need for urgent decisions on aviation capacity, while Sir Howard has admitted that the timetable could be construed as kicking the issue into "the long grass".