Red Wings Airlines, which lost its operating license in February after a plane crash, has been re-certified to perform maintenance work but is still not allowed to fly, former owner Alexander Lebedev said.
Lebedev announced the development late Sunday on Twitter, and the Federal Aviation Agency confirmed it Monday.
Aviation officials have until Sunday to decide to renew or annul the airline's flying license. It was unclear Monday whether they would do so.
"The company has not presented evidence that all violations and shortcomings have been entirely corrected," the Federal Aviation Agency said in a statement carried by Prime news agency.
The discount carrier Red Wings lost its operating license weeks after one of its 11 Tu-204 planes skidded off the runway and burst into flames while attempted to land at Moscow's Vnukovo Airport, killing five. The Federal Aviation Agency cited safety violations and the airline's financial troubles for its decision in February.
Lebedev, a Kremlin critic and billionaire whose National Reserve Bank has received paralyzing scrutiny from regulators, announced earlier this month that he had sold his 100 percent share of the airline to an unspecified group of investors for 1 ruble (3 cents).
The buyers were later identified by Kommersant as Mark Garber's GHP group and Sergei Kuznetsov, whose brother founded the Guta group.