Magna International aims to create a European-Russian automaker that produces up to 5 million cars a year, German daily Rheinische Post said, citing company sources.
Under its proposal, code-named Beam, the Magna would take over Opel jointly with Russian car company GAZ and the Russia state-run lender Sberbank to sell 1 million cars a year to the Russian market, the newspaper reported earlier this month.
Russia was on its way to overtaking Germany as Europe's largest car market before the economic crisis hit.
Russians like Opels - the brand ranked 11th in sales through April with volume of 15,506 cars.
Magna chairman and owner Frank Stronach has said that the supplier's Opel approach broke Magna's rule of not competing with the carmakers it supplies, but Opel's situation left him with no choice.
"I've always said our preference would be not to compete, but suppose some of our customers are broken? Then we might have no other choice," he told Canada's Globe and Mail newspaper.
Opel could make cars for other manufacturers if Magna becomes its partner, according to Automobilwoche, the German-language sister publication of Automotive News Europe.
Magna already has talked about the possibility with Ford Motor Co. or PSA/Peugeot-Citroen, Automobilwoche reported.
The magazine said Magna's idea is to establish an "open platform" that could be used by multiple manufacturers so that model series can be made efficiently right through their life cycles.
Magna does not plan to close any Opel factories in Germany, while it might shut plants in Antwerp, Belgium, and Luton, England.
Magna builds cars for Mercedes-Benz, Chrysler, Saab and BMW in Austria.