Nearly 1.2 million of Volkswagen's vehicles sold in the UK are fitted with the software behind the emissions scandal, the BBC has reported.
According to the broadcaster, the list includes "diesel-powered cars with the VW brand, Audi, Seat and Skoda as well as VW commercial vehicles". The BBC has a breakdown of the number of vehicles affected:
Volkswagen cars: 508,276
VW commercial vehicles: 79,838
Motorists have been told they must have their vehicles "corrected", but Volkswagen has not yet confirmed what the modification will involve.
The transport secretary, Patrick McLoughlin, told Channel 4 News: "The government's priority is to protect the public and I understand VW are contacting all UK customers affected. I have made clear to the managing director this needs to happen as soon as possible.
"The government expects VW to set out quickly the next steps it will take to correct the problem and support owners of these vehicles already purchased in the UK."
The company's chief executive, Martin Winterkorn, announced his resignation earlier this month after it was revealed that the automaker had fitted its diesel cars with software designed to cheat on emissions tests. He will be replaced by Matthias Müller, the boss of Porsche.
In the first four trading days since the scandal broke on 18 September, the company's shares fell by a third, cutting its value by €26 billion. German prosecutors have confirmed that they have opened an investigation into Winterkorn.
Around 11 million vehicles worldwide are believed to be affected, of which 500,000 were in the US. The UK is likely to be one of the worst-hit countries, with around 1 in 10 cars fitted with the technology. Nearly a million cars are believed to be affected in France.
The law firm Leigh Day has written to Matthias Müller to demand that the company refunds UK consumers the premium they paid for their "clean" diesel cars, as well as compensation for other losses.
According to the Guardian, the letter said:
Whilst we welcome the news that repairs will be undertaken to upgrade the affected cars to comply with EU nitrogen dioxide emission standards, such repairs may result in reduced fuel efficiency and increased CO2 emissions which in turn may impact upon the vehicle excise duty payable and other associated costs.
Our clients are also very concerned about the impact of the use of defeat devices on the resale value of their cars.
Some Volkswagen owners have expressed concerns about how the scandal could affect the resale price of their cars and the possibility of cars being worth less than their initial finance arrangements.
However, Alexis Cassey, a partner at independent dealership Prestige Diesels, told BuzzFeed News that she had seen no cause for concern so far: "I think the press have put it in a way that suggests people won't be able to sell their cars. But my partner has been to auctions twice this week and no Volkswagens had lost their value – they're still going through at the same value."
Dylan Setterfield, a senior editor at a manual referred to by used-car dealers known as CAP Black Book, earlier told the BBC that he did not expect any "significant impact" on used car values due to the scandal.
Alan White is a news editor for BuzzFeed News and is based in London.
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