Potential buyers of Air Berlin have until 15 September to submit their offers, the carrier has confirmed.
"Air Berlin will complete the investor process quickly," says the Oneworld member, which filed for insolvency earlier this month after shareholder Etihad signalled it was ending financial support.
Since then a number of airlines have either expressed an interest in acquiring all or part of Air Berlin or submitted a formal bid, including Lufthansa, Ryanair, TUI and German turnaround specialist Intro Group. EasyJet has also been linked with the process.
Separately, a regional court in Berlin says it will convene on 15 September to hear a complaint from Germania that a €150 million ($176 million) being provided to Air Berlin by the German government breaches European state-aid rules.
The court says Germania has called for the loan to be frozen until the European Commission gives its consent.