Germany took control of the Schwedt refinery, which was majority owned by Rosneft Deutschland, last Friday as Berlin strives to shore up energy supplies. It put Rosneft Deutschland under a trusteeship of the German industry regulator but Rosneft still holds 54% of the company's shares.

The German economy ministry is in talks with potential buyers, including a Polish company, two government sources in Berlin said. Reuters reported last week that Poland's top refiner PKN Orlen is interested in buying a controlling stake in Schwedt, which supplies 90% of Berlin's fuel.

Berlin is aiming to meet its European Union commitment to eliminate Russian oil imports by the end of the year, a move triggered by Russia's invasion of Ukraine.

The Schwedt refinery previously received most of its crude from Russia and Berlin is now looking to other countries to supply Schwedt.

"In Polish-German technical talks on additional oil supplies for Germany that are underway, the Polish side is declaring that potential help is possible under condition that Rosneft Deutschland is removed from the list of shareholders of PCK Schwedt," Polish climate ministry said in response to Reuters questions.

Germany's economy minister Robert Habeck said last week that talks with Poland on supplying oil for Schwedt were very advanced. Talks with Poland continue, his ministry said on Thursday.

"Our Polish friends have welcomed the decision to put Rosneft Deutschland under trusteeship. This gives us new opportunities for cooperation and we are happy to continue our talks," a spokeswoman at the economy ministry said.

Rosneft has said it could go to court to challenge Berlin's decision to take the firm's German subsidiary under trusteeship.

(Reporting by Marcus Wacket and Marek Strzelecki; Editing by Susan Fenton)

By Markus Wacket and Marek Strzelecki