Uber barred from London, ruled 'not fit and proper' to operate

London's transport authority announced Friday that it will not renew Uber's license, saying the company is not "fit and proper" to operate in the city.

Transport for London cited the company's approach to reporting serious criminal offenses, and its use of software that prevented regulators and law enforcement from monitoring the app.

London mayor Sadiq Khan said he "fully supports" the decision to not renew the license when it expires September 30.

"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 in a statement. "Providing an innovative service must not be at the expense of customer safety and security."

Uber said in a statement that it would "immediately challenge this [decision] in the courts."

It can continue to operate while it appeals.

"Transport for London and the mayor have caved in to a small number of people who want to restrict consumer choice," Uber said. "If this decision stands, it will put more than 40,000 licensed drivers out of work and deprive Londoners of a convenient and affordable form of transport."

About 3.5 million Londoners have used Uber.

London's traditional "Black Cab" taxi drivers have been among the most vocal opponents of Uber and have campaigned to convince politicians and residents to steer clear of the American firm.

Uber has sparked numerous controversies in major global cities over passenger safety, background checks and driver pay.

Uber operates in nearly 700 cities around the world.