Hundreds of people have gathered to demonstrate against the possible expansion of Heathrow Airport.
Mayor of London Boris Johnson and Zac Goldsmith MP for Richmond Park and North Kingston have spoken at the rally in Barnes, south-west London.
Last September, the government launched a review of how the UK might expand its airport capacity in the South East.
One long-standing option has been to add a third runway at Heathrow.
Heathrow is one of the world's busiest airports, handling more than 69 million passengers a year.
Mr Johnson said the expansion of Heathrow would be a "giant step backwards for London", giving rise to "great flying fleets of fortissimo flatulence".
He told BBC London the alternatives offered by Gatwick, Stansted and two sites in the Thames Estuary should be concentrated on, and the idea of Heathrow expansion "closed down".
He said Prime Minister David Cameron was keeping his cards close to his chest.
He added: "I think my party, the Conservatives, would be utterly nuts to go into the next election with the possibility of a Heathrow third runway on the table."
Conservative MPs Mr Goldsmith and Justine Greening, MP for Putney, Roehampton and Southfields. also spoke to protesters.
Sean McKee, director of policy at London Chamber of Commerce, said London is a "global city in an island economy".
He said there was a race between European capitals to see who could connect and trade with Asia, Africa and South America, and Heathrow provided the best opportunity.
Mr McKee said: "I think it's quite simplistic for those local politicians in west London to claim that everybody inside their boundary opposes Heathrow expansion.
"Overwhelmingly, our members say they want to continue flying from Heathrow because it gives them the connections they need."
But one resident, who has lived in Kew for 10 years, told BBC London the noise from flights already affects people's health.
"With an extra runway the respite we get either in the morning or the afternoon could disappear," he said.
"Night flights are the biggest bane of my life. The 04:30 flight comes in, wakes us up and we're all up for the day so there's a health issue here as much as anything else."
A commission chaired by ex-Financial Services Authority boss Sir Howard Davies, is to consider a number of options to expand capacity, including a new airport to the east of London.
The commission will report after 2015.
A spokeswoman for the Department for Transport said: "Previous attempts to tackle the question of airport capacity have failed, often due to a lack of consensus on the evidence.
"Our approach is to build a strong political consensus so we can plan for the future. A rushed decision is not an option."