Russian airline Aeroflot has withdrawn from the bidding for a substantial stake in Italian carrier Alitalia.
Aeroflot's exit leaves just one bidder remaining
It said it took the decision because it had been denied access to "critical information" about the firm's position.
The only declared remaining bidder for the stake in loss-making Alitalia is a group led by Italian airline Air One.
The bid process has been clouded by uncertainty over Alitalia's true financial situation, and its shares were suspended after Aeroflot's move.
Italian ministers have given interested parties until 12 July to make legally binding offers for the stake - up to a maximum of 49.9% - it plans to sell.
The deadline had been extended by 10 days amid concerns about the status of the remaining suitors and their bids.
Aeroflot said it had pulled out because it had been unable to obtain "critical information with respect to the commercial and operational aspects of Alitalia's business".
Air One, which is being backed by banking group Intesa Sanpaolo, has suggested it wants to bring on board other partners.
A combination of industrial problems, fierce competition and poor cost control has left Alitalia in trouble and in need of fresh investment.
Ministers have stipulated that the airline must retain its Italian identity and retain key routes.