Russia’s Gaz group, owned by billionaire Oleg Deripaska, will on Wednesday announce that it is buying a 50 per cent stake in Italian diesel engine producer VM Motori, which it will co-own with General Motors.

Gaz is buying the stake from Penske Corporation of the US for an undisclosed sum. The deal will have the blessing of GM, which owns the other 50 per cent of the Italian company, and controls its management.