Zac Goldsmith has said he will not stand as a Conservative MP at the next election if the party supports a third runway at Heathrow Airport.
The Richmond Park and north Kingston MP opposes the runway, arguing that the focus should be on improving how Heathrow manages its flight capacity.
But fellow Tory MP Tim Yeo said a third runway was necessary for Britain to remain economically competitive.
A consultation on UK aviation is due to report back in the summer.
Speaking to the BBC's Sunday Politics Show, Mr Goldsmith said: "If we were to stand at the next election with a manifesto which includes a third runway, I suspect that a number of what are existing Conservative seats would no longer be Conservative seats in this area."
Quality of life
Mr Goldsmith, who is a well-known environmentalist and was the editor of the Ecologist magazine for nine years, added: "I wouldn't stand as a Conservative on that manifesto, it's just not something I would do.
"I suspect there are others who feel the same way."
London Mayor Boris Johnson also opposes a third runway at Heathrow, but has campaigned for a new airport in the Thames Estuary which has been dubbed "Boris Island".
Aviation minister Theresa Villiers said she had concerns about the environmental impact of a third runway and the potential for it to damage people's quality of life.
"I don't see any technological solution on the horizon which could see us change our minds," she said.
"I see us opposing a third runway," the Conservative MP for Chipping Barnet added.
Mr Yeo, MP for Suffolk South and a former environment minister, believes Heathrow needs to expand so Britain has an international airport that is even more globally connected, particularly to expanding markets such as in Asia.
"We have to have good links to them if we are to remain competitive," he said.