Nearly a quarter of a century after the Berlin Wall came down and 14 years after the government moved back to Berlin as the unified capital, Germany is still struggling to open an international airport to replace two from its Cold War past.

The opening of the Berlin-Brandenburg Airport had been re-scheduled to October 2013, after already being postponed several times already over the past year due to problems, for example, with its fire safety systems.

"There will be no opening this year," the source told Reuters, confirming reports in German media. The source said no new opening date had been scheduled yet.

The delays have been a headache for Germany's second-biggest airline Air Berlin (AB1.DE) in particular, which plans to use the new airport as a hub for lucrative intercontinental flights.

The airport aims to attract up to 27 million passengers a year initially, making it about half the size of Germany's main airport in Frankfurt and less than a third the size of the world's busiest airport in Atlanta.

The saga surrounding the airport has tarnished the image of Berlin mayor Klaus Wowereit, a Social Democrat who had made it his flagship project and who sits on its board.

Wowereit, known for his charismatic smile and popular touch, has governed Berlin since 2001. Germany's first openly gay politician, he won re-election for a third term last September.

He gave the city its hip slogan "poor but sexy", and helped lure film and music companies, overseeing the transformation of Berlin from cold war outpost to bohemian hotspot for culture, night life and affordable living.

Opposition politicians in the Berlin assembly were quick to criticise Wowereit for not informing them of the latest postponement, despite apparently having been already aware of it in December.

The parliamentary leader of the Greens, Antje Kapek, called for a special meeting of the Berlin assembly this week, for Wowereit to explain himself.

The spokesmen for both Wowereit and the airport operator were not available for immediate comment. (Reporting By Holger Hansen; Writing by Sarah Marsh; Editing by Tim Dobbyn)

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