“The chief executive Rickard Gustafson has really done an impressive job. SAS has made a lot of improvements to the company,” he told the Svenska Dagbladet newspaper.
“It means that we could perhaps consider once again whether an acquisition could be possible.”
Lufthansa has long been seen as the main contender to acquire the ailing airline.
Franz did not reveal whether Lufthansa had begun talks with the three Scandinavian states (Sweden, Denmark and Norway) that together control 50 percent of the company.
“I’m not answering yes or no to that question. I’ll only say that I’m very impressed by what SAS has done in the past year,” he said.
“A Lufthansa purchase of SAS is something that has been discussed back and forth for many years… A few years ago a deal was nearly made but it fell apart, partly due to SAS’s bad finances.”
Both airlines are among the heavyweights in Star Alliance, the world’s biggest airline network which includes United, Turkish Airlines, Air China and ANA among others.
In November 2012 SAS announced a restructuring plan which its chief executive described as the “final call” to turn around the loss-making company.
The governments of Sweden, Norway and Denmark have indicated that they are interested in selling their shares in the airline if an attractive offer is made.