A scheme to scrap polluting vans in London has been extended to include more small businesses.

Mayor of London Sadiq Khan earmarked £23m in February to help charities and micro-businesses – those with ten or fewer employees – move to more sustainable vehicles.

But sole traders – people operating their own single-person businesses – were not eligible for the scheme, as many are not registered companies.

Transport for London has now updated the rules , allowing all sole traders to apply.

Under the scheme, micro-businesses and charities can replace up to three polluting vans.

£3,500 is available for vans which have been driven in the Congestion Charge zone at least once a week for the last year, or for vans that will be replaced with less polluting diesel vehicles.

Businesses or charities replacing their vans with electric vehicles will receive £6,000.

The initiative follows the introduction of London’s Ultra Low Emission Zone in April, covering the same area as the Congestion Charge. Older and more polluting vehicles pay £12.50 a day to drive in the area.

Liberal Democrat assembly member Caroline Pidgeon, who raised the exclusion of sole traders with the Mayor last month, welcomed the change.

She said: “It was a serious anomaly in the van scrappage scheme designed to help small businesses to exclude some of the smallest businesses and traders in London.

“Sole traders will often find it hard to go out and buy new and cleaner vans, so it is vital that they are given some help to make the change. On this issue the Mayor was right to put his hands up and admit that van scrappage needed to be adapted."

Speaking on the subject at Mayor's Question Time in May, Sadiq Khan said air pollution was "a national public health crisis" .

He said: "We realise many sole traders who are working hard were not eligible because they are not limited for a variety of reasons, and they want to do the right thing."