Sir Sadiq Khan is facing a legal challenge as councillors mount a fightback against a key policy.

The Mayor of London wants to pedestrianise Oxford Street - the city's most famous shopping destination.

But Conservatives at Westminster City Council have said they plan to challenge Sir Sadiq’s proposal at a March 5 budget meeting.

The Greater London Authority (GLA) is consulting on banning traffic on a 0.7-mile stretch of the street. The £150million policy includes the creation of a Mayoral Development Corporation (MDC). This would grant the Mayor more planning powers.

Sir Sadiq told MyLondon after being accused of "railroading" locals with the scheme: "We'll work with the council.

"It's not an issue of bypassing the council. We're working with the council.

"But you've got a street here that contributes £22billion towards the local economy, the national economy, the city's economy, 500,000 visitors a day.

"So we've got to make sure we work with the council, with the Government, with businesses to get the best possible deal we can for this street.

"I don't believe anybody can sensibly be happy with the status quo. I wasn't a fan of the Marble Arch Mound. I'm not sure anyone else was."

“The mayor is still ploughing on regardless of public opinion locally," Paul Swaddle, councillor for the Regent’s Park ward and Conservative group leader, told the Telegraph.

He added: "I think [it shows] a great arrogance, and he’s treating Westminster council and even the Westminster Labour group with contempt.

“We do not think pedestrianisation will work for Oxford Street. Until someone comes up with a way to mitigate its impacts, there’s no way we can support it, and I don’t support the way he’s doing it.

"There was already a plan and now we have a plan that will not deliver anything until 2026 or 2027 at the earliest.”

Tim Lord, of The Soho Society, a residents’ association, said: “The path to hell is paved with good intentions. This is the wrong idea, implemented in the wrong way for the wrong reasons.

"Part-pedestrianisation will increase congestion across London and it’s already the slowest city in Europe."