Westminster council’s last-minute effort to delay the pedestrianisation of Oxford Street has been rejected by the Government.

The town hall wrote to ministers last week demanding that Transport for London carry out a full environmental impact assessment before Lord Sadiq Khan’s £150 million project goes ahead next month.

TfL sought permission to forego the full evaluation, but the local authority argued that plans to ban traffic from the capital’s flagship shopping street would lead to an increase in noise and pollution in surrounding roads.

Councillors raised concerns the scheme was being rushed through without standard checks that assess the impact of major developments.

But minister’s rejected Westminster’s request on Friday.

Deputy council leader Tim Barnes said: "We’re extremely disappointed that MHCLG [the Ministry of Housing, Communities and Local Government] has ignored legitimate concerns about the impact this scheme will have on central London.

"Rushing pedestrianisation to meet the Mayor’s arbitrary deadline will be a disaster for local people, businesses and visitors.

“The Mayor’s own submission to MHCLG showed air pollution and noise rising. We need to know how much, and how far, those problems will spread.

"Important questions - on managing traffic, noise and impact on air quality all sit unanswered.

"We’ve consistently said that if pedestrianisation must happen we’ll help to make it work. London deserves a world class shopping district but I’m worried we’re heading for an unmanaged mess.”

He added that the council was reviewing the details of the decision and considering its next steps as work begins on the scheme.

Traffic is set to be banned between Orchard Street and Great Portland Street by the end of October and a permanent design for the new layout of the road, likely to include al fresco dining areas, is set to be published by November 2027.

The Conservatives, who won back control of Westminster council at the May 7 local elections, have repeatedly torn into Lord Khan for what they described as a “sham” consultation over the changes.

The Mayor believes pedestrianisation will boost Oxford Street’s attractiveness to shoppers, visitors and tourists and his office has previously rejected the Tory accusations that the project is being rushed.

TfL has said it submitted an environmental impact assessment screening opinion to the Government in “accordance with the legal requirements”.