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BERLIN, Sept 8 (Reuters) - Germany extended its trusteeship over Rosneft's local assets for six extra months on Friday, after no progress in negotiations with the Russian oil company on a settlement.
Berlin placed Rosneft's German assets, including its 54.17% stake in Berlin's Schwedt refinery, under a trusteeship last September in the wake of Russia's invasion of Ukraine.
In March, the German government extended this to Sept. 10, after winning a lawsuit by Rosneft challenging the measure.
Berlin wants to find a reliable buyer for the Rosneft stake, and in April the lower house of parliament approved changes to a law that would allow a quick sale.
But the Russian energy firm and Berlin have made no progress over an exit deal, delaying the search for potential investors, two sources familiar with matter told Reuters.
Rosneft has not immediately replied to a request for comment on the trusteeship extension.
Poland has been pushing Germany to force Rosneft out to clear the way for investors like Polish refiner PKN Orlen , which had expressed interest in a controlling stake.
The refinery is also owned by Shell and Italy's ENI with 37% and 8% stakes, respectively, and Shell has been also looking for potential buyers for its share.
Negotiations over the sale of Shell's stake are well-advanced, with an interesting offer from a private Polish company, sources said. Meanwhile, talks with state-controlled Orlen and the German side have stalled amid concerns about anti-German sentiment ahead of coming Polish election, they said.
Shell declined to comment.
Economy Ministry State Secretary Michael Kellner said Berlin was still very interested in expanding cooperation with Warsaw at the refinery, which is currently receiving shipped oil through the ports of Rostock in Germany and Gdansk in Poland.
"We are working very well with the Polish side," Kellner told Reuters.
Relations between Berlin and Warsaw have clouded with Poland's national-conservative PiS party playing an anti-German card ahead of October elections.
With some shipments from Kazakhstan, two Kazakh companies, KazMunayGas and its subsidiary Kaztransoil, could be possible future owners of the refinery, another source told Reuters, adding that firms have also expressed interest in Shell's stake.
The Kazakh companies could have an advantage in supplying the refinery with Kazakh oil, which is most compatible for Schwedt as it has the same chemical consistency as Russian crude, the source added.
KazMunayGas and Kaztransoil did not immediately reply to requests for comments.
Germany has welcomed Kazakh oil deliveries, but is concerned about possible disruptions through a pipeline via Russia, the source said, adding that Berlin was looking for an investor that could guarantee a production level of 75% in Schwedt. (Reporting by Andreas Rinke, Riham Alkousaa in Berlin, Olzhas Auyezov in Almaty, Vladimir Soldatkin in Moscow and Marek Strzelecki in Warsaw; Editing by Miranda Murray and Alexander Smith)