Ferrovie dello Stato, U.S. airline Delta andinfrastructure group Atlantia have been discussing how to revive Alitalia for months, pushing back various previous deadlines for making a firm proposal.
A binding offer is due to be presented by Oct. 15, but sources have told Reuters there is still no final accord on abid among prospective investors.
A spokesman for the German carrier declined to comment onLufthansa's letter and reiterated the airline had always saidt hat the Italian market was important.
The spokesman also said the carrier would be interested inAlitalia only once restructured, adding Lufthansa could imagine a commercial partnership with the Italian airline.
(This story refiles to correct date in dateline)
(Reporting by Stefano Bernabei in Rome and Hans Seidenstueckerin Frankfurt; Editing by Nick Macfie)