Volkswagen is considering legal action against its former chief executive Martin Winterkorn for negligence over his part in the Dieselgate emissions scandal, a spokesman for the company said on Sunday.

Mr Winterkorn is already facing criminal charges in the US over his role in the affair, although the case is unlikely to go to trial as Germany does not extradite its citizens.

But a civil lawsuit from VW could potentially ruin him, according to German legal experts who said the company could seek damages of more than €100m (£88m).

“The investigation has been going on for quite some while and is conducted independently of the authorities’ investigation,” Michael Brendel, a spokesman for the VW supervisory board, said.

Mr Winterkorn was VW chief executive in 2015 when it emerged that the company had rigged software on 11m cars to enable them to cheat emissions tests. He initially tried to cling on to his position but resigned five days later saying he was “utterly sorry”.

Invetsigations over his role in the affair in the US and Germany have centred on how much he knew about the emissions rigging. He has always maintained he was completely unaware it was going on and that he resigned because he “accepted responsibility for the irregularities” as chief executive.