Banning new petrol and diesel vehicles by 2040 will not deal with the current "public health emergency" caused by illegal air pollution, the Government has been warned.
Ministers unveiled their court-mandated plans for meeting legal European Union limits on harmful nitrogen dioxide pollution, much of which comes from road transport particularly diesel vehicles, after a long-running legal battle.
They include a £255 million fund to help local authorities come up with ways to improve air quality, ranging from improving public transport and changing road layouts, to charging zones for polluting vehicles if other measures are insufficient.
But much of the focus was on plans to end the sale of all conventional petrol and diesel cars by 2040, to help tackle air pollution and climate change emissions.
Air pollution causes an estimated 40,000 premature deaths a year in the UK and linked to health problems from childhood illnesses to heart disease and even dementia.
The Government was ordered to produce new plans to tackle nitrogen dioxide after the courts ruled previous proposals were insufficient to meet EU pollution limits, with draft proposals published in May and the final plans on Wednesday.
Environmental law firm ClientEarth, which took the Government to court to force action on air quality, said the final version of the plans appeared to be "little more than a shabby rewrite of the previous draft plans" and lacked urgency.
Chief executive James Thornton said: "The Government is passing the buck to local authorities to come up with their own schemes as an alternative to clean air zones which charge the most polluting vehicles to enter our towns and cities.
"Yet Defra's own evidence shows that charging clean air zones would be the swiftest way to tackle illegal levels of pollution."
He said the courts had ordered action by the UK to obey its own laws as soon as possible, but the plan kicked the can down the road again.
"The 2040 diesel and petrol ban, while important, is a diversionary tactic and doesn't deal with the public health emergency caused by illegally polluted air, now," he said.
Campaigners' calls for charging zones have been backed up by an assessment published alongside the draft plans which suggested they were the most effective measures to tackle nitrogen dioxide.
The Government acknowledges in the clean air plan that moves by local authorities to tackle pollution could include restrictions such as charging zones or moves to prevent certain vehicles using particular roads at particular times.
But it said councils should exhaust other options before imposing charging, and restrictions should be time-limited and lifted as soon as air pollution is within legal limits and there is no risk of future breaches.
Environment Secretary Michael Gove said: "Today's plan sets out how we will work with local authorities to tackle the effects of roadside pollution caused by dirty diesels, in particular nitrogen dioxide.
"This is one element of the Government's £3 billion programme to clean up the air and reduce vehicle emissions."
The plans also include looking at bringing in a "targeted scrappage scheme" focused on drivers who need most support, such as those on lower incomes or living next to a clean air zone.
The £255 million implementation fund will support work for councils to deliver plans within eight months to address poor air quality in the shortest possible time.
A clean air fund will be set out for councils to bid for money to introduce new measures such as changing road layouts to cut congestion, reducing idling vehicles, new park and ride services, concessionary travel schemes and improving bus fleets.
Measures would be funded by taxes on new diesel cars alongside existing departmental budgets, the plans say.