Uber collected over 730,000 signatures by Monday to protest London’s decision to not renew the company’s taxi license, a setback in one of its most lucrative markets.

The campaign on the website Change.org asks London Mayor Sadiq Khan to reverse Transport for London’s Friday decision, and is being promoted on the company’s app in London.

While the ride-hailing app is targeting 1 million supporters, Mr Khan defended his position that while he supports innovative businesses, all companies must adhere to high standards of safety and security.

“I have every sympathy with Uber drivers and customers affected by this decision but their anger really should be directed at Uber,” Mr Khan said in a response posted on the website Saturday.

“They have let down their drivers and customers by failing, in the view of TfL, to act as a fit and proper operator.”

Uber said 3.5 million Londoners rely on Uber for “a safe, reliable and affordable ride” and that 40,000 drivers depended on the app for their livelihood.

The company said its drivers have been “through the same enhanced background checks as black cab drivers.”

While the petition doesn’t trigger any legal or regulatory process, the San Francisco-based company has a history of successfully using petitions and loyalty of the public to pressure city governments.

It succeeded in reversing regulatory decisions in London and in New York in 2015. 

Uber urged customers to sign the petition in a tweet posted on  Friday, about two hours after the London agency’s decision.

Uber has 21 days after the 30 September revocation to file an appeal. It can continue the service until the end of the appeals process.