Transport secretary Patrick McLoughlin has called on the EU to conduct a full investigation into emission defeat devices.

He said: “The government takes the unacceptable actions of VW extremely seriously.

“My priority is to protect the public as we go through the process of investigating what went wrong and what we can do to stop it happening again in the future.

“We have called on the EU to conduct a Europe wide investigation into whether there is evidence that cars here have been fitted with defeat devices.

“In the meantime we are taking robust action. The Vehicle Certification Agency (VCA), the UK regulator, is working with vehicle manufacturers to ensure that this issue is not industry wide.

“As part of this work they will re-run laboratory tests where necessary and compare them against real world driving emissions.”

Meanwhile, PSA Peugeot Citroen and BMW have told reporters they are not affected by the emissions scandal.

A BMW spokesman said: "The BMW Group does not manipulate or rig any emissions tests. We observe the legal requirements in each country and fulfill all local testing requirements.

"In other words, our exhaust treatment systems are active whether rolling on the test bench or driving on the road.

"Clear, binding specifications and processes are in place through all phases of development at the BMW Group in order to avoid wrongdoing.

"Two studies carried out by the ICCT have confirmed that the BMW X5 and 13 other BMW vehicles tested comply with the legal requirements concerning NOx emissions. No discrepancies were found in the X5 between laboratory-test and field-test NOx emissions."

A PSA spokesman said: "PSA complies with the approval procedures in effect in all countries where it operates, and that engine settings, assuming the same conditions of use, are identical whether for approval procedures or in real life."