Sadiq Khan says capital will not be included in the chancellor’s £220m clean air fund despite having 40% of the most polluting roads in England and Wales

London cannot bid for a £220m clean air fund announced in the budget – despite being home to 40% of the most polluting roads in England and Wales, Sadiq Khan revealed on Thursday.

Giving evidence to the Commons joint inquiry into air quality, the mayor of London revealed he was lobbying the government to support a £515m London-based two-year diesel scrappage scheme.

But while the government was now talking about diesel scrappage schemes as part of the new clean air fund announced by the chancellor, Phillip Hammond, on Wednesday, the capital would not be able to seek money from the fund to set up the scheme.

“London, we found out last night, cannot bid for that. So there are 40% of the most polluting roads in London and we cannot bid for that money,” said Khan.

A spokeswoman for the Treasury explained that the capital was not eligible for funding: “London has devolved settlement. The clean air fund is for those local authorities who don’t have a devolved arrangement.”

Khan told MPs he had been lobbying the government to bring in a diesel scrappage scheme to support people to move away from using diesel vehicles to walk, cycle, use public transport or switch to electric cars.

The chancellor did not include any such scheme in his budget, either for the capital or the rest of the country. But he announced a fund of £220m to help with local air quality plans.

Khan said the scrappage scheme he was seeking support for was targeted at the poorest families, small businesses and charities.

He said: “It would involve 130,000 vehicles, including 70,000 vans from small businesses. For a car there would be a £2,000 contribution, £3,500 for vans and £1,000 for black taxis to get rid of the most polluting vehicles.”

Khan said he was in talks with the Treasury and Department of Transport, and questioned the government’s commitment to improving air quality because they had failed to include the capital in the £220m clean air fund.

Alan Andrews, lawyer for the environmental legal group ClientEarth, said the UK government had left local authorities “high and dry” by failing to mandate a national network of clean air zones in its latest air quality plans, which would keep the most polluting vehicles out of the most polluted town and cities.

“Local authorities can’t solve all these problems themselves, there needs to be national leadership,” he said. “The government’s new air quality plan doesn’t commit to doing very much at all. It’s really a plan for more plans.”

ClientEarth is making a third legal challenge to the government over its air quality plans. The government has twice been ordered by the courts to deal with illegal pollution urgently and previous plans have been found by the courts to be so poor as to be illegal.

Facebook Twitter Pinterest A public march in support of better air quality in the capital. Photograph: Mike Kemp/In Pictures/Getty Images

He said the new 2017 air quality plan only focused attention on 23 local authorities which were conducting feasibility studies, but failed to deal with Wales, or 45 English local authorities which all breach legal limits for air pollution. It also fails to mandate five local authorities which had been ordered to introduce clean air zones in the previous plan, but are not under orders now.

Andrews said: “Everyone knows that charging clean air zones are the only way to solve the problem of illegal air pollution in our towns and cities and the government needs to mandate them and focus on giving people a helping hand in moving to cleaner forms of transport.”

He added that the government had missed a “golden opportunity” in the budget to force the motor manufacturers to pay for a scrappage scheme after the VW emissions scandal, as had been done in Germany.

“Why has Angela Merkel secured €550m out of the car industry to pay for a clean air fund, whereas the £220m announced by the chancellor yesterday is going to be paid for by taxpayers?” he said.

Khan and Andrews called for a new clean air act which would give citizens a legal right to clean air and set up new legal powers to replicate EU directives and create an independent enforcement agency post Brexit.