Owners of old diesel cars should be able to scrap their vehicles for cash in pollution hotspots, the chairman of an influential Commons committee is expected to tell ministers.

MP Neil Parish is expected to use a House of Commons debate on Wednesday to urge the government to commit to a targeted scheme to tackle emissions.

He will say that 'households should not just be able to trade in multiple diesels for a cash subsidy', and instead the government 'should particularly consider targeting a scrappage scheme at poorer households or those earning less than 60% of the median UK household income'.

Mr Parish, Conservative chairman of the Environment, Food and Rural Affairs select committee, will say: 'If the government earmarked £500m for this scheme, it would take nearly 10% of the five million dirtiest diesels off our roads.'

It comes before the government publishes its updated clean air plans later this month, after courts ruled that existing plans to meet EU-mandated air quality limits are not sufficient.

There had been speculation that the plans would include a scrappage scheme aimed at taking older, more polluting diesel cars off the roads and replacing them with cleaner vehicles.

A poll by the AA last month found that 68% of drivers would support a diesel scrappage scheme, with just 10% of motorists opposed to it.

Mr Parish will suggest families could swap their polluting cars for low emission-producing vehicles, public transport tickets, bicycles or a car club membership.

Concerns over the impact of diesel cars on nitrogen dioxide levels were raised by the Volkswagen emissions scandal in September 2015.

A subsequent Department for Transport investigation found that 37 top-selling diesel cars exceeded the legal limit required for laboratory pollution tests when driven for 90 minutes on normal roads.

Drivers were encouraged to switch away from petrol under Tony Blair's government and Prime Minister Theresa May has said that would be taken 'into account' in future plans.

During a recent trip to the Middle East, Mrs May said: 'In relation to the issue of diesel cars, obviously we will be producing a new air quality plan, we've been required to do that by the courts.

'Decisions will be taken when we produce that plan - obviously we will take final decisions as to what we do.

'But I'm very conscious of the fact that past governments have encouraged people to buy diesel cars and we need to take that into account when we're looking at what we do in the future.'