Uber continued been one of the most popular ride-hailing apps in London, despite the ongoing case. (Photo: AFP)

Uber has won a legal bid to restore its London operating license, which was taken away by the city's transport regulator over safety concerns, after a judge decided on Monday that it was a "fit and proper" operator.

Transport for London (TfL) refused to grant the Silicon Valley-based company a new license in 2019 due to what it called a "pattern of failures." Uber argued it has since dealt with concerns over insurance verification and driver identification.

The U.S.-based company was also denied a license by TfL in 2017, a major blow in one of its most important markets, before a different judge restored it on a probationary basis.

"Despite their historical failings, I find them, now, to be a fit and proper person to hold a London PHV [private hire vehicle] operator's license," Judge Tan Ikram noted in his written verdict.

"I do, however, wish to hear from the advocates on conditions and on my determination as to the length of a license," he said.

Uber, which has apologized for mistakes it has made, has run into regulatory barriers and a backlash in other countries, forcing it to withdraw from some markets.

Shares in Uber rose six percent in pre-market U.S. trading after the decision.