Alexander Dobrindt, the German minister said: "We have been informed that also in Europe, vehicles with 1.6 and 2.0 litre diesel engines are affected by the manipulations that are being talked about," adding it is unclear how many vehicles in Europe were affected.

Mr Dobrindt added random tests would be carried out on cars made by other manufacturers.

The controversy involving VW is centred on "defeat devices" it used to fool US emissions tests on diesel cars into believing the vehicles met environmental standards.

The company admits the software, which switches engines to a cleaner mode during official testing, may have been fitted in 11 million of its vehicles worldwide. VW has not responded to Mr Dobrindt's claim.

Ireland's Road Safety Authority (RSA) has released a statement which says that it it monitoring the situation and waiting until the European Commission indicated if the company also cheated in European tests.

It reads, “The RSA notes the recent disclosure by Volkswagen in relation to its testing of vehicle emissions to the appropriate American standards.

"It is our understanding that the European Commission is determining whether the European Emission Standard Testing has been affected by Volkswagen's announcement and the RSA is being kept abreast of same."

At least 482,000 cars are to be recalled and the car maker could face penalties of more than $18bn (£11bn) in the US alone.

Volkswagen will start firing people responsible for manipulating the tests on Friday, two people familiar with the matter have told the Reuters news agency.

The sources said the carmaker's supervisory board will not only reveal a successor to chief executive Martin Winterkorn at the meeting, but will give initial findings from an internal investigation into who was responsible.