Transport for London (TfL), the capital's transport authority, has banned the Ola Indian taxi app over public safety concerns.
The taxi company has been operating in London since February.
TfL said the company has reported a number of breakdowns, including more than 1,000 trips made by unlicensed drivers.
Ola said she will appeal the decision and has 21 days to do so. It can operate in the meantime, according to the appeal rules.
The transportation authority said Ola did not report the faults as soon as she learned of them.
"Through our investigations we found that flaws in Ola's operating model have led to the use of unlicensed drivers and vehicles in more than 1,000 passenger journeys, which may have put passenger safety at risk," Helen Chapman, TfL's director of licensing, regulation and charging, she said.
"If they appeal, Ola can continue to operate and the drivers can continue to make reservations on Ola's behalf. We will scrutinize the company closely to ensure passenger safety is not compromised."
Uber win
The ride-hailing company started operating in Cardiff in 2018 and has since spread to other locations in the UK.
"We have worked with TfL during the review period and have tried to provide assurance and address the issues raised in an open and transparent way," Marc Rozendal, Ola's UK Chief Executive Officer, said in a statement.
"Ola will take the opportunity to appeal this decision and by doing so, our pilots and drivers can be confident that we will continue to operate normally, providing safe and reliable mobility for London."
Last week, main rival Uber secured the right to continue operating in London after a judge granted its appeal against TfL.
The ride-hailing giant got a new license to work in the capital, nearly a year after TfL rejected its application, including over safety concerns due to unlicensed drivers.
The Westminster Magistrates' Court heard 24 Uber drivers shared their accounts with 20 others, which resulted in 14,788 unauthorized rides.
