The £78m will be shared between 27 organisations who will build 3,000 homes with "flexible ownership options" across the capital, the first of which will be available in April. The scheme is expected to support around 6,000 construction jobs and to benefit around 10,000 Londoners.
An announcement of how the remaining £22m of funding will be allocated will be made next month, said Johnson in a statement.
The funding is part of the Mayor's Housing Covenant, which was launched in September last year and which aims to stimulate housing supply and help the market work better for low and middle income earning Londoners.
"Boosting construction and improving the housing options of hard-working Londoners is critical to this city’s economic success," said Johnson. "There has been a fantastic level of interest in this new fund, which will help an additional 10,000 people make their way onto the property ladder on top of those already being helped through other programmes."
"There is still much more that must be done to continue to boost house building in London, and I will continue to push for a fairer funding deal which puts us in an even stronger position to meet the challenges that lie ahead," Johnson said.
The announcement follows the Mayor's recent call on the Government to allow London to retain all stamp duty receipts raised on its property sales, which Johnson said would help the building of the one million homes needed in the capital over the next 25 years.
