A £220m bid to expand London City Airport has been turned down by the mayor after more than 1,000 people objected to it.
Boris Johnson has instructed Newham Council to refuse the application on noise grounds.
The airport sought permission to create more parking spaces and build new taxiways for larger planes.
Planning permission was granted by the council in February but was subject to the mayor’s approval.
The council had said permission included conditions to help limit the noise disturbance, such as imposing flight restrictions, erecting a noise barrier and funding soundproofing packages for residents.
However a spokesman for the mayor said he believed the scheme would have lead to an “unacceptable increase in noise for East Londoners” without benefitting the city.
He said the mayor was also unwilling to expose East London to an increase in noise on the basis that he had already argued it would be unacceptable for West London if Heathrow Airport were expanded.
The mayor believed the “only long-term option” to balance the airport capacity issue with residents’ quality of life, was to build a new hub to the east of of the city, he added.
London City Airport said it was “perplexed and disappointed” by the mayor’s decision.
It said expansion would have increased London’s airport capacity, created up to 1,500 jobs, and attracted a further £750m for the UK economy.
John Stewart, chairman of HACAN East that campaigned against the expansion plans, said the group “salutes” the mayor’s decision.
“The airport is paying the price for being so cavalier about noise,” he said.