Sadiq Khan has vowed to press ahead with his expansion of the Ultra low emission zone (Ulez) on August 29, despite Labour losing a crucial by-election in an area affected by the plan.

The mayor said he was “disappointed” by the result – which has been widely interpreted by many as a Ulez protest vote – but that extending the clean air zone London-wide continued to be “really important”.

“We know every day that there are people dying prematurely,” said Mr Khan.

“There are children with stunted lungs because of air pollution, adults with a whole load of health issues. 

“So we’re going to carry on doing what we can to support Londoners [with the expansion].

“But the reality is that actually 95 per cent of Londoners who drive a car in inner London have a compliant vehicle. In outer London, it’s around 90 per cent.

“Clearly, we need to make sure that more Londoners with non-compliant vehicles have the support they need.”

Mr Khan said he would “carry on listening” to Londoners about the expansion.

Ham & High: Sir Keir Starmer speaking to the media during a visit to Shefford in Mid Bedfordshire where he urged the London mayor to 'reflect' on Ulez Sir Keir Starmer speaking to the media during a visit to Shefford in Mid Bedfordshire where he urged the London mayor to 'reflect' on Ulez (Image: PA)

He has pointed to City Hall’s decision at the start of June to widen the eligibility criteria for the scrappage scheme, which meant all Londoners receiving child benefit could apply, as well as a larger number of businesses.

The widened criteria also mean London-based charities will be able to scrap or retrofit up to three vans or minibuses, instead of just one.

Labour Party leader Sir Keir Starmer has blamed Sadiq Khan’s charge on polluting vehicles for Labour’s narrow defeat in Boris Johnson’s old seat, but said the party stands by its green pledges.

Camden Town councillor Danny Beales lost the Uxbridge & South Ruislip by-election last week by just 495 votes, despite telling a hustings on July 6:  “It’s not the right time to extend the Ulez scheme to outer London, it’s just not.”

Former prime minister Boris Johnson held the west London seat with a majority of 7,210 in 2019.

Sir Keir Starmer,  MP for Holborn and St Pancras, told broadcasters during a visit to Shefford in Bedfordshire on Saturday (July 22): “I don’t think there is any doubt that Ulez was the reason that we lost the election in Uxbridge,”

“And I have said we should reflect on this, including the mayor. I have spoken to him as you would expect, and so there will be that reflection.”