Some 400,000 people have signed a petition urging Transport for London (TfL) to reverse its decision not to renew Uber's licence, the media reported on Saturday.
On Friday, the regulator said Uber was not "fit and proper" to hold a London private hire operator licence on the grounds of "public safety and security implications", the BBC reported.
The ride-hailing app firm has said that it would appeal against TfL's decision.
The petition, started by Uber London, says: "If this decision stands, it will put more than 40,000 licensed drivers out of work and deprive millions of Londoners of a convenient and affordable form of transport."
TfL's concerns include Uber's approach to carrying out background checks on drivers and reporting serious criminal offences.
The licence was due to expire on September 30.
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It has 21 days to appeal against TfL's decision and can continue to operate while any appeals are ongoing.
A petitioner from London told the BBC that he added his signature because: "Uber provides a much needed alternative to minicabs and black cabs. It is more efficient, safer and economical than the alternatives."
A Twitter user said that she was "annoyed" at the decision as Uber allowed her to get out of "uncomfy" situations if out at night.
Some 3.5 million passengers and 40,000 drivers use the Uber app in London.
--IANS
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