In the US, over two dozen car models made by BMW, Chrysler, General Moors, Land Rover and Mercedes-Benz are to be investigated by the EPA as it widens its investigation of VW to cover other carmakers.

According to the Financial Times, the inquiry will cover at least 28 diesel-powered models to see if the manipulation of emissions tests is a widespread industry practice.

It added that the tests will initially cover one vehicle of each model and will be expanded if anything suspicious is found.

The news comes as the UK Government announces that it is extending its investigation into manipulated emissions tests to include all carmakers, but said owners of affected vehicles won't be penalised with Vehicle Excise Duty rises.

Working with the Vehicle Certification Agency and Driver and Vehicle Standards Agency, the Department for Transport will soon begin laboratory and real-world emissions tests on Volkswagen Group models already confirmed to contain the software.

It added that there was no evidence that a ‘defeat device’ had been used elsewhere, but ongoing testing will now include other manufacturers, aimed at finding out whether the issue is more widespread.