German government assistance for the European division of General Motor Corp.'s (GM) is far from certain, given "many open questions," economics minister Karl-Theodor zu Guttenberg said Saturday.

His comments followed a conference call with governors of the German states of North Rhine-Westphalia, Rhineland Pfalz and Hesse, where factories of the German GM unit Opel are located.

A key issue to resolve is how independent Opel would be from its parent company in the U.S., zu Guttenberg said.

On Friday, GM's European unit said it will present a plan on how to save the company in Berlin on Monday. GM Europe President Carl-Peter Forster, speaking at the Opel brand headquarters near Ruesselsheim, said Opel requires EUR3.3 billion in capital.

German politicians are under pressure from labor unions to bail out Opel, GM's largest European brand by far, to help save the company's 25,000 jobs - a number that more than doubles when including parts suppliers and other Opel-linked companies.

-By Beate Preuschoff, Dow Jones Newswires, +49 (0)30 - 2888 4122, beate.preuschoff@dowjones.com