City Hall funding for major estate regeneration in London will only be provided if residents vote in favour of the changes, the mayor has proposed.
Under the scheme, ballots for residents on projects where demolition is planned would become a condition for mayoral funding, Sadiq Khan suggested.
Mr Khan said he wanted to make sure those living on social housing estates "are at the heart of any decisions".
The Conservatives said the announcement "smacks of pure cynicism".
Launching his guide to housing estate regeneration, Mr Khan said he wanted to use his investment powers to give more say to residents.
Under the proposal, ballots will apply to schemes funded by the mayor's office that involve the construction of at least 150 homes.
The mayor said that while he has limited sway over estate regeneration, he wanted to "use my investment powers in a way they have never been used before".
"We need more social housing in London, not less, which is why I will use all my powers to make sure that any plans for estate regeneration protect existing social housing," he said.
Conservative London Assembly Andrew Boff said Mr Khan had "consistently flip-flopped on this issue and refused to be drawn".
"The fact he's finally settled on a position in favour just weeks before his potential re-selection smacks of pure cynicism and self-interest," he said
Green Party London Assembly member Sian Berry welcomed the announcement but accused the mayor of being "slow to bring out his guidance" having originally provided a draft in December 2016.
A public consultation on the proposals will run until 3 April.