Sadiq Khan will pledge to lobby Labour ministers for investment in new transport projects in London costing billions of pounds.

The capital’s mayor will make the commitment in a speech on Wednesday night, in which he will declare that “when London builds, Britain benefits”.

Mr Khan wants to secure funding to extend the Bakerloo Tube line from Elephant & Castle to Lewisham.

A Transport for London document published in February stated that the estimated cost of the project would be between £5 billion and £8 billion.

The mayor will seek investment for a new rail service named the West London Orbital on existing lines in west London.

The most recent published capital cost estimate of the scheme was £273 million in 2017/18 prices.

Mr Khan wants funding for extending the Docklands Light Railway from Gallions Reach to Thamesmead, which has previously been expected to cost around £1.7 billion.

He will also attempt to secure a long-term funding packages for TfL, after the previous Conservative government only issued short-term deals.

In the speech at the London Transport Museum’s annual dinner at Guildhall, Mr Khan will say: “Over the course of this mayoral term, we’ll pursue a long-term funding deal for TfL to give us the capacity to reach for the future once again.

“And I will – as promised during my re-election campaign – use my position as Mayor to lobby for more transport investment in our city.

“This includes the DLR extension to Thamesmead, the West London Orbital and the Bakerloo line extension.

“Projects which would create new jobs, generate good growth, and taken together lead to the construction of tens of thousands of homes for Londoners.

“So, this is our vision. Now our task is to find the determination and forge the partnerships to realise it.”

On Thursday, Mr Khan will attend the opening of Siemens’ new train factory in Goole, East Yorkshire, where most of London Underground’s new Piccadilly line trains will be assembled.