Transport for London (TfL) has made a formal application to funding ministers to extend the Docklands Light Railway (DLR) across the river in east London.
He presented a strategic case to the government for the extension of the line from Gallions Reach to Thamesmead via Beckton Riverside and under the Thames.
The body told ministers the proposal, which would be a third leg of the DLR River, could unlock the construction of 30,000 homes, create 10,000 jobs and improve connectivity.
London Mayor Sadiq Khan, Transport Commissioner Andy Lord and Greenwich Council leader Anthony Okereke were among those backing the plan.
The latest documents submitted by TfL call for government funding to help build a full business case and move the project towards construction.
Khan said: “Extending the DLR would unlock huge opportunities for London. It would support tens of thousands of new homes, provide new transport links and boost the economy, supporting the creation of thousands of jobs.
“Investment in our transport network is key to building a better, fairer and more prosperous London for everyone.”
Lord added: “By extending the DLR from Gallions Reach to Thamesmead via Beckton Riverside, we can provide two new accessible stations. [and] connect two major growth areas and four development sites at once, bringing more homes, retail, leisure activities and unlocking more of London for those who live, work or visit the city.
“We have seen what can be achieved with investment in public transport which has brought transformative change over the last few years with the Elizabeth line, the extension of the Northern line to Battersea and the extension of the London Overground to Barking Riverside. This case of strategic scheme is the next step on the way to make this scheme a reality”.
TfL hopes to agree an affordable solution by 2025, start construction in 2028 and open the new part of the line to passengers in the early 30s.
A spokesman for the Department for Transport said: “We continue to engage with the Greater London Authority on the business case for developing Thamesmead and Beckton Riverside, and are carefully reviewing the proposals.”