A major benefactor of the deal would be British energy giant BP, which has been hit with massive costs incurred as a result of the disastrous oil spill in the Gulf of Mexico.
Rosneft is in "advanced negotiations" to buy a 50 percent stake in the German oil refiner Ruhr Oel from state-owned Petroleos de Venezuela for between $1 billion to $2 billion, the Wall Street Journal Europe reported.
The other half of Ruhr Oel is owned by BP, which has a right of first refusal on its Venezuelan partner's holding.
"In exchange for waiving that right, BP has been offered a lucrative deal by Rosneft to explore for oil in the Arctic Ocean," the newspaper said, quoting people familiar with the matter.
Founded in 1983, Ruhr Oel controls refineries with total capacity of 23.4 million tonnes of crude oil per year, according to its website.
It owns two refineries directly and parts of two others in Germany that together account for one quarter of all German refining capacity, the report said.
The German unit of BP that manages operations at Ruhr Oel was not immediately available for comment.