Up to six parties other than Fiat, including sovereign wealth and private equity funds, remain interested in General Motors Europe, two people close to the Detroit carmaker said on Monday.

As Sergio Marchionne seeks to sell his vision of a pan-European, transatlantic car group to German politicians, he faces tough talks ahead with GM and the US government task force overseeing its restructuring on issues of control, financing, and joint operations at the proposed new company.