The Volkswagen, Audi, Skoda and Seat networks will begin the recall programme to update emissions controlling software on 2.0TDI EA189 engined cars next month.

And the carmaker has confirmed that there will be an “attractive package” put in place to compensate its UK customers for any reduction in the value of their car.

But Volkswagen AG’s management expect the challenge of rebuilding consumer trust to be a longer process for the carmaker. Some 450 people are conducting the internal and external investigations, and at a press conference today, Hans Dieter Pötsch, chairman of the supervisory board of Volkswagen AG, said the company was “deeply shocked” by the events which have “put the group in a very difficult situation”.

He said Volkswagen relies on the trust of its customers, investors, employees, politicians and the public, and it “deeply regrets” the emissions scandal.

Pötsch added: “No business transaction justifies overstepping legal and ethical bounds."

Early results of the group’s internal examination of the processes indicate that the software-influenced NOx emissions behaviour was due to the interaction of three factors: The misconduct and shortcomings of individual employees; weaknesses in some processes; and a mindset in some areas of the company that tolerated breaches of rules.

The company has already drawn a key conclusion based on findings, namely that its testing practice must undergo comprehensive changes.

Volkswagen has decided that in the future emissions test will be evaluated externally and independently. In addition, randomly selected real-life tests to assess emissions behavior on the road will be introduced.

Pötsch stated: "We hope that this will help Volkswagen regain lost trust."

He said the indication is that a small group of employees were responsible for the emissions test defeating technology. As a first step, nine managers who may have been involved in the manipulations were suspended.

Pötsch added: "I here and now guarantee that we will pursue our thorough investigation to its conclusion. I vouch for this personally, as does the entire supervisory board of Volkswagen AG."