LONDON (Reuters) – Uber’s new boss Dara Khosrowshahi apologised to Londoners for the taxi app’s mistakes and pledged to make changes as the Silicon Valley firm tries to overturn a decision to strip it of its licence in one of its major markets.

The British capital’s transport regulator on Friday deemed Uber unfit to run a taxi service and decided not to renew its licence to operate, which will end this week, citing the firm’s approach to reporting serious criminal offences and background checks on drivers.

Mayor Sadiq Khan, a Labour politician who has criticised the firm in the past, said on Monday he had asked Transport for London (TfL) to be available to meet CEO Khosrowshahi.

Uber’s 40,000 drivers, one third of the city’s total number of private hire vehicles, will continue to take passengers until an appeals process is exhausted, which is likely to take several months.

London police complained this year that the app, which is backed by Goldman Sachs and BlackRock, was either not disclosing, or taking too long to report, serious crimes including sexual assaults and that this put the public at risk.

“It’s … true that we’ve got things wrong along the way. On behalf of everyone at Uber globally, I apologise for the mistakes we’ve made,” Khosrowshahi wrote in an open letter to Londoners.

“We will appeal the decision on behalf of millions of Londoners, but we do so with the knowledge that we must also change,” he said.

The loss of the San Francisco-based start-up’s licence in one of the world’s wealthiest capitals comes after a tumultuous few months that led to former CEO and co-founder Travis Kalanick being forced out.

Khosrowshahi, who is less than a month into his new job, did not specify which mistakes Uber had made in London.

Uber’s UK head of cities, Fred Jones, said the firm was working with the police to work out how it can better report incidents.

He also said TfL, which declined to comment on Monday, had not been clear about it concerns.

“Once we understand them we can work with them to figure out what is it that they would like us to do and how can we move forward and I think that’s the important next step,” Jones told BBC radio.

‘ARMY OF LAWYERS’

Khan, who backed TfL’s decision, said the transport body was open to meeting Uber’s boss but attacked the Silicon Valley company’s response to losing its licence.

“I appreciate Uber has an army of lawyers, they’ve also made aggressive threats about taking us to court and the rest of it,” he told BBC radio.

“You can’t have it both ways: on the one hand acting in an aggressive manner for all sorts of things but on the other hand brief to journalists that they want to do a deal with TfL,” he said, adding companies that played by the rules were welcome in London.

The firm has until Oct. 14 to formally appeal TfL’s decision and the case is likely to be filed at Westminster Magistrates’ Court in London.

Uber, which began operating in London in 2012, has faced regulatory and legal setbacks around the world amid opposition from traditional taxi services, and has been forced to quit several countries including Denmark and Hungary.

However, it has also managed to overturn bans and other crackdowns.

Earlier this year, Italy briefly blocked Uber from operating, citing unfair competition, but lifted the prohibition a week later, while in Taiwan it resumed services in April after talks with the island’s authorities, ending a two-month suspension.

A petition calling on London to overturn its decision not to renew Uber’s licence had gathered more than 750,000 signatures at noon on Monday.

“This ban shows the world that London is far from being open and is closed to innovative companies, who bring choice to consumers and work opportunities to those who need them,” the petition says.