Tom Copley, deputy mayor for housing, was speaking at a London Assembly meeting last Thursday.
Responding to a question from Unmesh Desai AM about the importance of transport infrastructure for housing development, Mr Copley said: "We have been pushing very strongly for the Bakerloo Line extension and in expectation of the Bakerloo Line extension an awful lot of development and planning applications are going in along the Old Kent Road.
"I'm very sorry to say that there are there are more and more sites around there that are stalling now because we haven't got the Bakerloo Line extension and we desperately desperately need that.
"I don't just say that as a Lewisham resident - because ultimately it will come down to Lewisham and we hope, one day, maybe through Catford down to Hayes - but this is essential.
"TfL is now only able to fund about three quarters of its capital investment programme for this year.
"And so we absolutely desperately need Government support for these critical projects."
In 2019 TfL warned that only 9,000 of the 25,000 new homes planned for the Old Kent Road area can be built unless or until the Bakerloo line extension is in place.
Last month Southwark Council leader Kieron Williams gave an upbeat assessment of the prospects for the Bakerloo line extension, saying that an updated business case for the scheme is "looking really positive".