Diesel drivers will be paid to scrap their cars to improve air quality.

Diesel drivers will receive compensation to encourage them to scrap or “retrofit” highly polluting vehicles under Conservative plans to reduce emissions to be unveiled later this week.

The Government will on Friday publish its new air quality strategy which will include plans for a “targeted” diesel scrappage scheme, The Telegraph has learned.

Ministers will also consult on plans to give people help with retrofitting older, more polluting diesel vehicles to reduce the levels of harmful nitrogen dioxide that they emit.

The Conservatives will warn local authorities against imposing pollution taxes on motorists amid concerns that doing so would “punish” motorists and become an election issue.

It comes after Theresa May, the Prime Minister, said last month that she was “very conscious” that motorists were encouraged to buy diesel cars under Labour more than a decade ago because of concerns about carbon emissions.

A Conservative source said: “We will help drivers on modest incomes who bought their diesel vehicles in good faith, having been badly advised by the last Labour Government. We are cleaning up Labour’s mess.”

The Government has been forced to come up with tougher measures to target diesel drivers after losing a case against environmental campaigners ClientEarth over breaches of EU emissions standards.

Last week a High Court judge rejected an application by the Government to delay publication of its strategy until after the general election. Ministers have decided against making an appeal.

The new strategy had led to concerns that diesel drivers would be targeted with charges of up to £25 a day to enter “clean air zones” in seven towns and cities. They include Leeds, Nottingham, Southampton and Derby.

While councils will have the power to impose pollution taxes, ministers have warned them that they must examine all other alternatives first.

A party source said: “We are clear that measures other than charging zones should be preferred if they are as effective at reducing pollution. We are not mandating any council to levy charges on private cars and motorbikes. Councils will need to justify any policy to their electorate.”

Instead of pollution taxes, councils will be urged to improve the flow of traffic with measures such as removing speed humps to prevent cars repeatedly slowing down and speeding up, which almost doubles the amount of harmful gasses they pump out.

Other options which are expected to be put forward include better sequencing of traffic lights to ensure that drivers will keep arriving at green lights rather than red ones if they drive within the speed limit. The Conservatives will announce a consultation on a “targeted” diesel scrappage scheme

Under the plans car owners will only be able to qualify for cash to scrap their diesel vehicles if they are old enough and registered at an address where air pollution is already at dangerous levels.

A previous scheme in 2009 allowed a vehicle to be scrapped for a £2,000 discount on a new car, with £1,000 from the manufacturer and £1,000 from the Government.

Ministers will also consult on a retrofitting scheme, which is likely to be targeted at white vans and other more polluting vehicles. Drivers would be given grants to adapt their exhausts to reduce pollution levels.

The Conservatives will blame Labour’s “poor advice” for encouraging people to buy diesel cars as part of a drive to reduce carbon dioxide emissions. 

The number of diesel vehicles on Britain’s roads has risen from 3.2 million in 2000 to more than 10 million today after the Labour Government slashed fuel duty on diesel cars in a drive to reduce carbon dioxide emissions. 

It has since emerged that diesel vehicles emit harmful nitrogen dioxide, which can raise the risk of strokes, heart attacks and asthma attacks.

Senior Labour figures including Sir David King, who served as Tony Blair’s chief scientific adviser, have since admitted that they were “wrong” to promote diesel cars.

Barry Gardiner, the shadow environment minister, has said: “There’s absolutely no question that the decision we took [on diesel] was the wrong decision. Certainly the impact of that decision has been a massive problem for public health in this country.”

The Tories will warn that Labour would hit “ordinary working people” with pollution taxes. The party has pledged to bring in a new “clean air act” that would introduce a set of “common standards, tariffs and penalties across the country”.

Other proposals in the white paper are expected to include “real driving emissions” vehicle tests in the wake of the Volkswagen emission scandal and encouraging the public sector to buy cleaner vehicles.