Berlin's new airport delayed again

"This further delay is the result of problems with the fire protection system, in particular the fresh air supply in the case of a fire and the complexity of the system as a whole," the airport management explained on its website, adding it was "too early" to set another deadline.

Cooling pipes totalling a length of some 60km were not insulated properly. Others already built in walls which now have to broken up and re-built, airport sources told Tagesspiegel.

The giant project is now estimated to cost over €4 billion, double the initial estimate, and narrowly avoided bankruptcy in December when the European Commission approved a further German government cash injection under EU state aid rules.

Adding to the financial woes are potential fines, as Air Berlin, the country's second-largest carrier, in November decided to sue the airport for damages. Air Berlin currently flies from Tegel, where capacity is limited, and had hoped to boost its activity by 230 flights a week once the airport opens.

Both Air Berlin and Lufthansa, Germany's main carrier, are now asking for more investments in the infrastructure at Tegel airport, given that it will have to cope with the air traffic for longer than this year, when it was supposed to close down.

Mainly treated as a regional story, the airport flop may, however, dent the popularity of the opposition Social Democrats ahead of general elections in the fall. The mayor of Berlin, Social Democrat Klaus Wowereit, is now under pressure to resign.

Wowereit on Monday stepped down from the chairmanship of the airport's supervisory board, but said he would not give up his main mandate as a mayor. Another Social Democrat, Matthias Platzeck who is the governor of the Brandenburg region, has now taken over the airport responsibility, linking his political fate to it.

The conservative-liberal government has steered clear of putting the blame on its political rivals and is asking for the head of the main project manager, Rainer Schwarz.

The leading architects of the airport were fired in May and sued for €80 million damages. They claim the fiasco is not their fault as politicians have ordered some 500 changes to the initial plan, ZDF reports.