There's a serious risk Uber won't be allowed to operate in London
They are particularly worried about Uber's corporate behaviour, predominantly in the US where the firm is being investigated by the FBI for using secret software to evade local regulators.
A leaked letter that TfL board member Michael Liebrich sent questions Uber's alleged "regulatory evasion", its passenger safety record, and the way it rates passengers.
The newspaper quotes a second board member as saying: "My position is that we shouldn't renew the licence. I did raise concerns about the way Uber reportedly 'games' its application to deceive regulators, also issues around increasing congestion and private hire vehicle numbers."
Transport for London is responsible for licensing black cab and private-hire drivers, as well as private-hire operators like Uber.
It's under serious pressure either to revoke Uber's licence or to impose serious restrictions on the companywhen the firm's licence comes up for renewal at the end of September.
Former Uber drivers, black cab firms, the police, and MPs have all been hugely critical of the firm over the last two years, claiming that drivers end up out-of-pocket, and that Uber fails to adequately report sexual assault. They argue that Uber has unfairly wriggled around existing rules and regulation to the detriment of London's traditional black taxis.
Uber's licence actually came up for renewal earlier this year, and TfL granted the company a four-month licence. In the meantime, it launched a consultation on whether to hike up the fees for a private-hire operator licence.
That means that even if Uber wins a five-year licence, it could end up paying more than £2 million for its 40,000 drivers in the city.
Uber said in a statement to The Sunday Times: "Over 3m Londoners regularly use Uber. We want to continue to do so."
The news comes as Taxify, a cheap rival to Uber, had its licence revoked by Transport for London. The company has appealed the decision.