(Bloomberg) --

London mayor Sadiq Khan warned that an entire underground subway line could close if the city’s transport agency can’t access the “emergency and long-term funding it needs” from the U.K. government to maintain services. 

Transport for London would consider such a move as a last resort to deliver the savings needed to address the agency’s funding needs, Khan said in a statement on Tuesday. The capital city’s current emergency funding agreement with the government is set to expire Dec. 11. 

Khan didn’t mention which tube line could be shuttered. Without further aid, “bus services would have to be reduced by almost a fifth, and Tube services would need to be cut by nearly 10%,” he said.

TfL has already warned it may need to cut peak service on some underground lines if it cannot find ways to plug budget holes exacerbated by the Covid-19 pandemic. It said earlier this month that it can currently only afford a “managed decline” of services, where new investments, like fleet replacements and bus electrification, would be delayed. 

The transport agency needs to raise an added 500 million pounds ($667 million) to 1 billion pounds in revenue per year as part of a government funding package that kept services running.

The government has said that following previous funding agreements with TfL, it would work closely with the mayor to secure a deal that balanced the needs of London and interests of U.K. taxpayers after passenger revenue collapsed during the pandemic.

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