Struggling airline Air Berlin, Germany's second-biggest carrier, is on the hunt for investors and has already begun talks with potential partners from China or the Gulf, a German daily reported Friday.

Air Berlin chief Hartmut Mehdorn has already held talks with Etihad Airways, based in the United Arab Emirates, and Chinese holding company HNA, the main shareholder of Hong Kong Airlines, the Sueddeutsche Zeitung daily said.

One option is the "selling of a large amount of Air Berlin shares," the daily said, without citing its sources.

Air Berlin's founder, Joachim Hunold, had always ruled out the option of seeking foreign investors but new boss Mehdorn appears to be pursuing a different strategy.

Company shares were down 2.64 percent at 2.58 euros in early trading in Frankfurt on the news.

The airline, which relies heavily on transporting German tourists, ran into heavy turbulence in 2008 after years of soaring growth and expansion.

The firm has suffered more than its competitors from external factors, such as the political turmoil in North Africa since the beginning of the year.

It has also been hit hard by rising fuel costs, the introduction of an aviation tax in Germany and uncertainties over the economy.

It will be in the red this year and has not given guidance for 2012.

According to the Sueddeutsche, Etihad already tried to buy a slice of Air Berlin in 2008, without success.

HNA wants to boost its presence in Europe and was said to have been interested in Hungarian airline Malev as well as several airports controlled by German construction firm Hochtief.

Air Berlin wasn't immediately available for comment.