But this has nothing to do with the 'dieselgate' scandal that rocked the industry.

Instead, the European Commission says the carmakers colluded to curb the use of emissions-cleaning technology that they possessed.

Around a decade ago, the firms agreed not to compete over the use of AdBlue - a fuel additive that can clean emissions from diesel vehicles.

As a result, the Commission says they limited use of AdBlue, and thus didn't clean up emissions as much as they could have.

Mercedes-maker Daimler was also part of the cartel, but isn't being fined as it was the one to reveal its existence.

The Commission says all the parties have agreed to settle, and acknowledged their role in the group.

But VW says it is considering legal action.

The German giant says Brussels is punishing beneficial technical cooperation by treating it as an antitrust violation.

VW has already faced about $38 billion in fines and other costs related to the dieselgate scandal, when it was found to have cheated on emissions testing.