The opening of Berlin's new airport may be postponed for a fourth time — the latest delay in a project that has turned into a major embarrassment for German officials.

The Willy Brandt airport was originally slated to open in 2011. After two delays last year, it was supposed to open on Oct. 27, 2013. But Transport Ministry spokesman Sebastian Rudolph said Monday that officials were told last week airport managers see new "major" problems. He didn't elaborate.

Germany's Bild newspaper, citing internal documents, reported that the airport won't be able to open before 2014 at the earliest.

The airport project has been blighted by technical and planning problems, in particular with its fire safety system.