Sadiq Khan today unveiled plans for the 'managed decline' of London's transport system if he fails to secure a long-term funding deal from the government.
Transport for London said it needed a minimum of £1.7bn over the next 18 months to balance its books and a further £1.3bn every year for vital improvements.
Officials have drawn up a worst-case scenario which would see more than 100 bus routes axed, almost one in 10 Tube services cut and the possible closure of the Rotherhithe Tunnel.
Plans for new bike lanes would be scrapped along with the expansion of 20mph speed limits.
City Hall released a series of images showing shabby Tube stations and trains to illustrate its warning of a return to the underfunding of the past.
"Unless the Government provides the long-term funding needed to maintain our public transport network, there will be no choice but to make significant cuts to services just as demand is growing again," said Sadiq Khan.
"This would mean fewer, less frequent and more run-down bus and Tube services for Londoners, making it more difficult to travel around the city.
"It would also mean more road and tunnel closures due to a lack of funding to maintain key transport infrastructure.
"The widespread disruption and gridlock all these changes would cause would not only unfairly punish millions of Londoners for the impact of the pandemic on TfL's finances but would put the national economic recovery at risk," London's Mayor added.
But London Assembly Conservatives accused the mayor of "ridiculous scaremongering"."Sadiq Khan's ridiculous scaremongering is useless," said Susan Hall, Leader of the London Assembly Conservatives.
"Instead of playing politics, the Mayor should engage constructively with the government and do his bit to make savings.
"If Mr Khan were truly worried about service cuts, why on earth would he allow TfL to award £12 million in executive bonuses next year?", she added.
TfL has been given government bailouts worth almost £5bn since the start of the Covid pandemic but the most recent cash injection runs out on December 11th.Transport bosses said the post-pandemic recovery had been hit by a slower than expected return to work.
The income from the expanded Ultra Low Emission Zone was also smaller than anticipated.