Canadian-Austrian auto-parts maker Magna has asked Russia's GAZ to make a bid for a stake in General Motors' German carmaker unit, Opel, Russian Prime Minister Vladimir Putin has said.

Putin, speaking in an interview published on Sunday, said Russia would not intervene in a possible deal that German media say could be part of a plan to create a car giant that would produce up to 5 million cars a year.

Canadian-Austrian company Magna asked Russian financial institutions and GAZ to make a proposal to Opel, Putin said, according to a transcript of the interview with Japanese media provided by the Russian government.

These are commercial questions. Everything needs to be carefully calculated, Putin said. The Russian government is attentively following what is going on. German media have said Magna would take over Opel jointly with Russia's debt-laden carmaker GAZ and Russian state bank Sberbank.

GAZ and its owner, Oleg Deripaska, have repeatedly denied an interest in Opel. Sberbank has also denied any bid. GAZ and Sberbank were unavailable for comment during the Russian bank holiday weekend.

GM's planned sale of Opel has pitted Fiat against Austrian-Canadian Magna, and both companies have reportedly presented proposals to the German government.

GM Europe has said $1.2 billion worth of cost cuts could help Opel return to profit by 2011. It has also said it needed 3.3 billion euros ($4.4 billion) in state aid from European governments to avert job cuts and site closures.

German Chancellor Angela Merkel is under pressure to help Opel and save jobs to avoid mass layoffs in the run-up to a federal election in September.

(Reporting by Guy Faulconbridge, editing by Greg Mahlich)