VW global sales fell 2.4% in November 2015 following the emissions scandal, the German automaker announced on December 10.
The total for the 11 months of 2015 was down 4.5% compared with 2014.
The annual tally was likely to fall short of last year’s total as a result.
VW-brand board member Jurgen Stackmann said: “In view of the current challenging situation, I don’t believe VW will be able to make up the gap in the remaining days of the year.”
Sales plunged in Brazil, with a 51.4% fall, and slid by 31.8% in Russia, although economic problems in both countries were largely to blame for those declines rather than the emissions scandal.
The VW brand delivered 6.12 million cars in total in 2014.
The automaker said last week that US sales fell 24.7% in November compared with the same month last year.
Volkswagen group chairman Hans Dieter Potsch said on December 10 that a “chain of errors” led to the emissions scandal and that the entire company was now focused on regaining the trust of customers.
In September, US regulators found that some VW diesel cars had a “defeat device” – or software – to cheat emissions tests.
VW said the situation arose when it decided to launch a large-scale promotion of diesel vehicles in the US in 2005, but found it impossible to meet strict emissions limits in force in that country in time.
Hand Dieter Potsch said: “No business justifies crossing legal and ethical boundaries.”
VW CEO Matthias Muller said he was confident that customers would overcome their reluctance to buy the group’s vehicles in the coming weeks.