BBC London News has reported that part of Oxford Street will go traffic-free from 26 October, with the almost one-kilometre stretch between Orchard Street and Great Portland Street closed to buses, taxis and bikes.
Cross-streets running north to south will stay open, and emergency vehicles will keep access.
The Mayor of London told the BBC the scheme was needed because "we've seen good quality retail leaving Oxford Street" and "bad quality shops come to Oxford Street." Shoppers and shop workers interviewed on the street were broadly supportive, while black cab drivers were critical, one calling it "a horrendous idea" for people leaving shops with bags who need a taxi or bus, and another saying that "a lot of the local residents didn't want it, but they've been overruled."
Speaking live on the programme, Cllr Tim Barnes, Deputy Leader of Westminster City Council, said:
"It's great that we finally got a date in public from the Mayor for when traffic-free Oxford Street will commence, but we're still really worried about many of the critical issues of management of the street and for the area around, which really haven't been solved."
Cllr Barnes pointed out that a plan to invest around £120 million in Oxford Street, half from the private sector and half public, was already under way before the Mayor's scheme:
"Unfortunately, 20 million pounds of that had been spent by the time that he started, and that money was just wasted." He warned that pushing traffic onto side streets would put at risk the economic activity around Oxford Street, not just the shops on it.
The new Oxford Street Development Corporation says it will monitor how the space is used with real-time data.
Cllr Barnes said it must look at the whole area, from jobs and office and retail space to air pollution, adding:
"We still don't know adequately who's going to clean it, what the policing's going to be looking like, how the blue light services will make their way down, or who's even going to be able to take care of the pot plants on the street."
You can watch Victoria Hollins' full report on BBC London News via BBC iplayer.
