Deputy mayor for transport Heidi Alexander said that Tube station schemes, road maintenance programmes and the speedy roll-out of more cycle lanes were all at risk.
She said the requirement for TfL to make at least £300m of savings this year, to comply with the £1.08bn bailout deal accepted by Mr Khan last month, would make it harder to achieve its long-term aim of getting more Londoners out of their cars.
Full details of the projects to be abandoned are due to emerge over the coming weeks, prior to being agreed by the TfL board on July 28.
“I would be surprised if we went through this process and there were not a significant number of deferrals of individual capital projects,” Ms Alexander told the London Assembly transport committee. “That is the reality that the current funding settlement has created for us.”
Under the terms of the deal, fares will rise again in January by the RPI rate of interest plus one per cent – on top of a 2.6 per cent hike last March.
Asked whether the cuts would impact on the Mayor’s transport strategy, which seeks by 2041 to have 80 per cent of journeys walked, cycled or taken by public transport, Ms Alexander said they were likely to affect TfL’s ability to rapidly roll-out more safe cycling infrastructure.
She said: “At the moment we are involved in a discussion about which projects we are going to defer. We are still in the foothills of our thinking on this.
“I think the conditions of the funding deal will make it harder to achieve our objectives.”
She said Tube stations that had been severely over capacity pre-pandemic would not be able to be upgraded as quickly as previously hoped.
Work on Crossrail 2 has been suspended and unfunded projects such as the Bakerloo line extension and the Croydon tram extension to Sutton have been kicked into the next decade.
However there was the possibility that a proposed cross-river extension of the DLR to Thamesmead could move up the “pecking order” due to being more affordable than other options, she said.
Under the terms of the bail-out, TfL is required to work with the Government on reviewing the case for driverless trains on the Tube.
Ms Alexander described the concept as “a little bit of a fetish of the Prime Minister” and suggested removing on-board staff from deep-level Tube lines such as the Northern, Victoria and Piccadilly would breach fire safety regulations.
She said she was also keen to press ahead with plans to rename the individual lines on the London Overground, as proposed in Sadiq Khan’s mayoral manifesto.