The US giant did not disclose any details of the deal other than half of the company will remain with Penske Corporation. General Motors and VM Motori have already worked together on projects including the development of a 2.9 litre V6 diesel engine for GM's new Cadillac CTS saloon and more projects are said to be in the pipeline.

“Diesel engines have a very important role in GM's global advanced propulsion strategy,” said Tom Stephens, group vice president, GM global powertrain and quality. “We are leveraging expertise and resources within our company and through technology partners to ensure we develop the world's best powertrains.”