More than 1,500 new homes, including 450 affordable homes, will be created across the two communities, which will be known as East Wick and Sweetwater.
Schools, green spaces, business and creative space, leisure and community facilities will also be developed at the two sites.
Homes England has agreed a £78m loan from its Home Building Fund for the first four phases of the scheme, being developed by a joint venture between Balfour Beatty Investments and Places For People Homes on land owned by the London Legacy Development Corporation (LLDC).
It is anticipated that the first phase of the development will be completed in summer 2021, with work at East Wick and Sweetwater being fully completed by 2028.
Work has already begun on phase one of the site, which will include 130 new affordable homes and 105 for private rental, as well as more than 33,000 sq ft of business and creative space.