In total, VW has said that just under 11 million vehicles worldwide have the software 'defeat device' that was exposed in American emissions tests last month. While two-thirds are thought to be fixable with a software upgrade, it's believed that a total of 3.6 million affected VW, Audi, Skoda and Seat models - those featuring the 1.6-litre version of the EA189 turbodiesel engine - will require hardware changes to correct the issue. US models may require the addition of a urea tank, whereas European editions of the 1.6 are likely to need new fuel injectors.
VW's new CEO Matthias Müller has pledged that all affected cars will be fixed by the end of next year. He added: "Our most important task will be to regain lost confidence with our customers, partners, investors and the general public. The first step in this direction will be a fast and relentless examination and explanation. Only when everything comes to the table, only when things are completely explained, only then will people trust us again.
"Believe me, I too am impatient. But in this situation, in which we are dealing with four brands and many models, care is more important than speed.
"The technical solutions to the problems are in sight. By contrast, the business and financial consequences are not yet foreseeable."
VW, Audi, Skoda and Seat launch websites for owners to check if they are affected
Volkswagen, Audi, Skoda and Seat have launched websites that allow owners to check if their car is affected by the emissions scandal.
The VW site collapsed soon after launch as a result of the amount of traffic trying to access it, but has since been functioning normally. Sites from Audi, Skoda and Seat are all running without problem.
Government won't hike tax bills
The Government has confirmed that UK taxpayers will not be hit by a higher tax bill if it turns out that their cars were found to have cheated tests.
Transport secretary Patrick McLoughlin said: “The government expects VW to support owners of these vehicles already purchased in the UK and we are playing our part by ensuring no one will end up with higher tax costs as a result of this scandal.”
He also confirmed that the Department for Transport has pushed for more clarity on the matter and that the next round of tests will look at whether the software “is being used elsewhere”.
"Neither cars, nor the testing facilities will be provided by the vehicle industry themselves". VW has offered to pay for this testing if the government requests it does so.
VW's remaining EU5 stock taken off sale in the UK
Following the scandal, Volkswagen Group UK took 4000 cars fitted with the EA189 engine off sale, pending investigations into how it will remove the illegal software that cheated US emissions tests while still ensuring the cars comply with all emissions regulations.
The move covered vehicles from Audi, Seat, Skoda, Volkswagen, and the cars and commercial vehicles affected represent around 3% of the Group’s total UK stock. They are expected to be put back on sale once the Group’s modifications have been put in place.
A spokesman stressed that the decision to withdraw the cars from sale was a voluntary measure, rather than a regulatory one. The vehicles remained on sale beyond the September 1 deadline for Euro 6 emissions regulations to come in to effect because legislation allows manufactures to clear stock of Euro 5 engined vehicles. VW has previously confirmed all of its cars fitted with the latest, Euro 6-classified engines are fully legal.