"For over 90 percent of the Europe group's vehicles, solutions are now confirmed," he told around a thousand VW executives at the company's headquarters in Wolfsburg, northern Germany, without giving more detailed figures.

The carmaker has admitted to fitting 11 million diesel engines worldwide with sophisticated software fitted to skew the results of tests for nitrogen oxide emissions. That admission has triggered both regulatory and criminal investigations in several countries, including Germany and the United States.

Volkswagen has subsequently revealed that beyond the nitrogen oxide scam, it had also understated carbon dioxide emissions of 8,00,000 vehicles, including petrol cars. The carmaker, whose divisions include Audi, SEAT and Skoda as well as its truck and commercial vehicles, now faces the sizeable task of recalling 8.5 million vehicles throughout Europe.

Mueller has promised that the company would submit its recall plans to German authorities by the end of November. The fixes will range from simple software update for two-litre diesel engines, to more complex solutions for 1.6-litre models.