London’s transport regulator stripped Uber on Friday of its license to operate from the end of September. The decision will affect more than 40,000 drivers in a massive blow to the taxi app.

“Uber’s approach and conduct demonstrate a lack of corporate responsibility in relation to a number of issues which have potential public safety and security implications,” Transport for London (TfL) said.

Uber has the right to appeal the decision within 21 days.

Globally, Uber has went through a tumultuous few months after a chain of scandals involving allegations of sexism and bullying at the company, leading to investor pressure which forced out former CEO and co-founder Travis Kalanick.

In London, Uber has faced criticism from unions, lawmakers and traditional black cab drivers over working conditions, Reuters Reported.

The app has been forced to quit several other countries.

London Mayor Sadiq Khan said he backed the decision.

“All companies in London must play by the rules and adhere to the high standards we expect – particularly when it comes to the safety of customers,” he said.

“It would be wrong if TfL continued to license Uber if there is any way that this could pose a threat to Londoners’ safety and security.”

In a break with the startup’s usual combative tone, Uber’s new Chief Executive Dara Khosrowshahi asked London to please work with the ride service. He told employees the company needed to act with integrity but that he did not believe Uber had done everything it was accused of in London.