Uber lodged an appeal with a British court after the ride-hailing app lost its operating license in London, the company said on Friday.

The appeal hearing is likely to be on December 11, according to a spokesperson for the U.K. judiciary office. Uber said that the appeal was filed at Westminster Magistrates’ Court in London.

Last month, regulators Transport for London (TLF) failed to renew Uber’s license and gave the U.S. firm until October 13 to appeal. Uber waited until the deadline day to file the appeal. Uber can still operate while the appeal is ongoing.

“While we have today filed our appeal so that Londoners can continue using our app, we hope to continue having constructive discussions with Transport for London. As our new CEO has said, we are determined to make things right,” an Uber spokesperson said in an emailed statement.

London Mayor Sadiq Khan said TFL will defend its decision.

“The courts now will consider the appeal from Uber and of course TFL will defend the decision they made,” Khan said during a monthly question time session before the official appeal, Reuters reported Thursday.

TFL accused Uber last month of showing a “lack of corporate responsibility” in relation to “public safety and security”.

Last week, newly-appointed Uber CEO Dara Khosrowshahi flew to London to meet with TFL. Uber has been trying to placate the regulators. In an open letter after the ban, Khosrowshahi admitted that the company has “got things wrong along the way” and apologized for any mistakes. Khan, who is also chairman of TFL, praised the CEO and said he acted with “humility.”

After talks with TFL, Uber released a statement saying that it was a “constructive meeting” and that there would be further discussions in the coming weeks.

London is an extremely important market for Uber. The company claims to have 40,000 drivers in the U.K. capital. An online petition against TFL’s decision has garnered over 850,000 signatures.

But beyond the ban in London, Uber has faced further scrutiny over its employment and tax practices. A Reuters investigation last month found that Uber uses a loophole in the tax system to not pay value added tax (VAT) in the U.K. on the booking fees it charges.

And elsewhere, the company is waiting to hear the result of a U.K. employment tribunal appeal, which will rule on whether its drivers are classed as employees or are self-employed. If they are deemed to be employees, Uber may have to give them benefits such as paid leave. This could potentially boost the company’s operating costs.

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