Volkswagen has pledged to fix all cars equipped with illicit engine software in Europe by autumn 2017, the European Commission has said.
The Commission made the comments after talks with the car maker to ensure it is doing enough for affected clients.
At a meeting with consumer Commissioner Vera Jourova, VW board member Francisco Javier Garcia Sanz committed to a plan to inform customers by year's end of the need for a technical fix to bring diesel cars into line with EU caps on toxic nitrogen oxide (NOx) emissions, Jourova's spokesman said.
The German carmaker also committed "to have all cars repaired by autumn 2017," spokesman Christian Wigand said, adding the carmarker would offer clients "proof of conformity."
VW has admitted that it installed improper software that deactivated pollution controls on more than 11 million diesel vehicles sold worldwide.
EU officials have called on the German carmaker to do more to compensate European clients since its $15 billion settlement in the US for using the cheat software, saying it is unfair for them to be treated differently.
"Volkswagen committed to an EU-wide action plan today, which is an important step towards a fair treatment of consumers," Jourova said in a statement.
Volkswagen has rejected suggestions it may have breached EU consumer rules and said it does not see the need to compensate affected car owners.
Europe's largest car maker is making slow progress on fixing cars in Europe, having repaired less than 10% of the 8.5 million affected models in Europe.
It said the majority of the cars in Europe can be repaired this year, but an unspecified number will have to wait.
VW group models with 1.2 litre and 2.0 litre engines require only a software update on pollution control systems, but about 3 million 1.6 litre models also require a mesh to be installed near the air filter.