SADIQ Khan will ban driving in a large part of central London for a day in a bid to tackle pollution in the capital.
Critics though have called the move a “stunt” and was little more than a “virtue signal” which wouldn’t cut air pollution without long term action.
When does the ban take place?
The Mayor of London has revealed plans to tackle pollution in the capital with a car-free day on September 22 that will see part of the centre of the capital largely shut down.
12.3 miles of roads will be closed around Tower Bridge, London Bridge and the City of London, forcing commuters in the capital to walk or get the tube instead.
That's the equivalent of nearly 200 football pitches in length.
Buses will be allowed from London Bridge up to Bishopsgate but in other areas Londoners will be redirected or could even be forced into cabs to avoid the closures too.
Pedestrians will be able to walk and cycle down the roads instead, which will take place on a Sunday.
And boroughs across the city will hold events promoting cycling or public transport too.
Mr Khan said: "I encourage as many Londoners as possible to join in the fun and see the city from a different perspective.
"Many of us need to use the car. But we need to make sure people realise the alternatives."
It's the first time a London Mayor has shut down large sections of road in the city centre in this way.
What have the critics said?
Tory MP Greg Hands told The Sun: "Sadiq Khan is already doing his best to clog up London's streets with the three year closure of Hammersmith Bridge and other pinch points.
"We all want to do more to help the environment, but closing the city down for the day isn't the answer."
Mr Khan's Tory rival to be Mayor, Shaun Bailey, said earlier: “We all want to clean up London’s air and symbolism and stunts are fine as long as they’re matched with concrete action like cleaning up our dirty bus fleet and expanding our public transport network.
"What will get people out of their cars for good are reliable, green alternatives, not more taxes combined with fewer bus routes and delayed tube upgrades, which is this Mayor’s record."
And Keith Prince AM, GLA Conservative Transport Spokesman, added: “Londoners want cleaner air but car free days risk travel chaos if managed poorly while doing little to tackle air pollution.
"Instead of virtue signalling, the Mayor should focus on cleaning up TfL’s bus fleet quickly to improve air pollution on our streets.”
Green campaigners gave the news a cautious welcome but said it wasn't enough to tackle air pollution.
Earlier this year the Mayor brought in plans to charge a million drivers an extra £12.50 to try and stop them travelling through the capital with his Ultra Low Emission Zone.