Giving the go-ahead to a third runway at Heathrow airport could create 65,000 jobs.
The £9 billion expansion at the west London airport - expected to be given the green light by the Government this week - is vital for the UK economy, business and union leaders have said.
The leaders, all members of the pro-expansion group Future Heathrow, were speaking in London following their placing of newspaper advertisements calling for a third runway.
Paul Talbot, assistant general secretary of the Unite union said the runway work could create 50,000 new jobs and there could be another 15,000 new jobs once the project was completed.
The Government has consistently backed the expansion plan but the Conservatives are opposed to it as are a number of Labour MPs.
London Mayor Boris Johnson prefers the building of a new airport in the Thames Estuary but British Airways chief executive Willie Walsh said that such a plan was "a non-runner".
Mr Walsh said such a new airport could cost around £35 billion. He went on: "There is absolutely no way, even in good economic times, that the scale of investment required would be available. The only credible plan is to expand Heathrow."
Environmentalists, local residents and local councils are all opposed to the new runway at Heathrow.
The expansion of the west London airport will mean the loss of hundreds of homes including many in the village of Sipson.
Asked about the Sipson situation, Colin Matthews, chief executive of airport operator BAA said: "An airport brings good things and bad things. We can't avoid the bad things that come with expansion. No-one can possibly take any pleasure in the destruction that construction can cause."
