Uber is now allowing passengers across most of the UK to pay in cash.

Following trials, the cash payment option was this week extended to all UK cities, except London, where it is being reviewed.

But individual drivers can still opt out of accepting notes and coins, partly if they are worried about safety of carrying them in their vehicles.

The move came as a major report suggested shops and services might need to be forced to accept cash in the future to protect those who rely on it.

On Wednesday, the Treasury Committee of MPs stopped short of recommending mandated cash acceptance now, but said its report was "a wake-up call" to government on the issue.

Uber has become a huge company and dominates the global ride-hailing market, as well as operating in a host of other transport sectors. Its rapid ascent has come with controversy and protests from other taxi providers.

The taxi app's success has been based around new technology, but meant customers needed cashless payments to use its services.

Following pilots in Birmingham, Stoke, Nottingham and Leicester, Uber said it has now extended the option of paying in cash to other UK cities, because some people preferred paying in cash or did not have a bank card.

"We believe that movement should be accessible to everyone, so following successful pilots in some UK cities over the last 18 months, we have decided to give passengers outside of London the option to pay for trips with cash," a spokesman said.

Passengers can select cash as their payment option on the app. Drivers can opt out in preferences on their own app.

If they do not have enough change, that is given as a credit to the passenger by Uber.

The cash option is being reviewed by authorities in London, and remains unavailable for Uber Eats or booking for other forms of transport via the Uber app.

Cash campaigner Ron Delnevo from the Payment Choice Alliance said Uber's move "demonstrates that they now believe in the future of cash in the UK", and brought the company's operations in the UK in line with many other countries.

He called on the government to introduce a law that would force all shops and services to accept cash.

Ministers have said there are no plans to introduce such rules.

However, the Treasury Committee's recent report did highlight various groups who relied on cash, including some people with learning disabilities and those who use cash to keep to a budget.

Among those reliant on cash, and who gave evidence to the committee, were victim-survivors of domestic and economic abuse.

Many face the dangers of being traced by their abuser via the payments they make. Buying a train ticket, for example, could only be done with cash in order to avoid an abusive partner becoming aware of their movements.

"It really is a matter of life and death," said Sam Smethers, chief executive of the charity Surviving Economic Abuse. "Without it they find themselves monitored daily, with every transaction."

Joint bank accounts and mortgages had also been used as a way to impose coercive control over somebody, she said.

And cash could be used as an eventual escape route.

"One victim-survivor said she hid pockets of cash around her house until she had enough to flee her abuser," she said.

The charity would like to see cash acceptance backed by law, but Ms Smethers said she welcomed the focus the committee's report had put on the plight of those facing economic abuse.