The German government believes GM still wants to sell Vauxhall/Opel, following talks yesterday.
GM's management board "had made it clear" it is still interested in a buyer, a German official told the Reuters news agency.
The news follows reports that GM would hold on to its European operations, rather than sell them off to either Magna or RHJ International.
The sale is complicated because Magna wants to have access to GM's patents, something the company is loathe to allow.
However, the German government is not in favour of a sale to RHJ, fearing greater job losses, and has said it will make the terms of its bridge loan harder if GM picks the company as its preferred buyer.
If GM wants to hold on to Vauxhall/Opel it must pay back the bridging finance it has already received from the German government, which is said to top £1.5 billion. It will struggle to do this, as the US government money it has received is ring-fenced and cannot be spent on foreign operations.