All new petrol and diesel cars and vans will be banned from UK roads from 2040, the government will announce on Wednesday in a revised "controversial bomb" air pollution plan.

The Tory government published a draft air pollution plan in May, but it faced criticism from environment lawyers and clean air campaigners for being too floppy at curbing the nitrogen oxides (NOx) pollution that causes thousands of premature deaths in the UK each year. The High Court demanded that a final version of the plan be published by the end of July—and so here we are.

In addition to following in France's footsteps with an internal combustion engine ban by 2040, the plan mostly focuses on empowering local councils to make major changes to their road systems. Reprogramming traffic lights, removing or redesigning speed bumps (!) and roundabouts, and retrofitting buses are all being mooted as possible ways of reducing air pollution.

The plans, which were dished out early to national newspapers and broadcasters, seem to downplay the likelihood of creating dozens of new Clean Air Zones—special areas in the UK where motorists with polluting vehicles would have to pay a stiff daily charge, similar to London's incoming ULEZ. These charges would be seen as a tax on motorists with older petrol and diesel vehicles, and some people don't like new taxes. A source told the Guardian that Clean Air Zones aren't completely off the table, but the government wants to exhaust other routes first.

The plans would set aside £1 billion for ultra-low emissions vehicles, including £100 million for public electric charging infrastructure and plug-in car grants, and £290 million has been earmarked for retrofitting old public transport and propping up sales of hybrid taxis. Local councils will have access to an air quality grant, apparently. Cycling and walking gets a juicy £1.2 billion.

The government hopes that these plans, combined with the headline internal combustion engine ban in 2040, will be enough to assuage the naysayers—and, one assumes, to stop the air quality on some UK streets from being illegally poor. We'll know more once some scientists get their hands on the full air pollution plan.

ClientEarth, the group that originally pursued the government through the courts and won the High Court judgment, was cautiously optimistic about the new air pollution plan. The petrol and diesel ban is good news, but "the law says ministers must bring down illegal levels of air pollution as soon as possible, so any measures announced in this plan must be focused on doing that," CEO James Thornton told the Guardian.

London mayor Sadiq Khan echoed Thornton's sentiments, saying that Londoners can't wait for 2040. "Toxic air pollution is the biggest health crisis facing this generation," Khan said. Around 40,000 premature deaths per year have been attributed to the UK's poor air quality, at a total cost of around £27.5 billion. About 9,000 of those deaths are in London. Khan wants to introduce a diesel scrappage fund, which would give the owners of older diesel vehicles a few thousand pounds if they buy something new or use an alternate mode of transport.

Ars will update this story once the government's full air pollution plan has been published. We wouldn't be surprised if there are some hidden land mines in there.

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