The head of VW cars in the UK has apologised "unreservedly" for "significantly" letting down its customers in the diesel emissions scandal.
It comes days after the American boss of VW made a 'sincere apology' over the scandal which has affected more than 11 million cars worldwide.
The government is to launch an investigation into vehicle emissions following the VW testing scandal in the United States.
Transport Secretary Patrick McLoughlin said in a statement:
Volvo withdrew an app comparing cars' emissions in 2011, after being told by that the data "could not be taken seriously".
Volkswagen's US boss has admitted he was told in spring last year of the emissions cheating affecting millions of the company's vehicles.
Volkswagen could start recalling cars containing emissions cheating software in January, according to the firm's new chief executive.