Nearly a quarter of a century after the Berlin Wall came down and 13 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.

Berlin-Brandenburg Airport, which will also be known as Willy Brandt Airport after West Germany's Cold War chancellor, had been scheduled to open on June 3. But the airport's operator said the move from the city's Tegel airport was suspended with immediate effect.

"It's not a good day for airport Berlin-Brandenburg Willy-Brandt, not a good day for the citizens ... and the many visitors to our region," Berlin mayor Klaus Wowereit told a news conference.

Matthias Platzeck, state premier of the neighbouring Brandenburg region, said he now hoped the airport would be open in the second half of August, after the school holidays in Berlin and Brandenburg.

The opening of what will be Germany's third largest airport after Frankfurt and Munich, has been postponed once already.

Platzeck, who said he was "livid", expects the airport management to set a new date by next Monday.

The 2.5-billion-euro airport will replace Tegel in west Berlin and the old east Berlin airport of Schoenefeld to the southeast, and initially aims to attract up to 27 million passengers annually. The two existing airports, which are due to be shut down, will handle all flights until the new airport is ready.

The airport's technical chief, Manfred Koertgen, said fire safety installations - notably smoke extractors - were in place but it was doubtful whether they could be operational, or passengers evacuated safely in an emergency, by the June 3 deadline.

To avoid a repeat of the technical problems that hit the opening of Terminal 5 at London's Heathrow airport in 2008, the operator of all airports in Berlin, Flughafen Berlin Brandenburg GmbH FBB.L, has been rehearsing for opening day for months.

It has recruited more than 10,000 local volunteers to try out the check-in and baggage handling - using suitcases filled with bricks to make the tests realistic - and report back on how easy it is for passengers to find their way around.

As recently as last Friday, when foreign journalists were given a tour, construction workers in hard hats were scurrying around a site with dangling cables and other building materials, but officials were confident of a smooth opening on June 3.

"We've gone through six months of testing with a total of 10,000 extras and 20,000 staff employees going through dry runs," an airport spokesman told reporters then.

One of the first challenges for the airport was to be handling passengers travelling to Poland in June for the Euro soccer championship.

FIRE SAFETY

Mayor Wowereit said it would have been irresponsible to stick to the opening date, even if it could theoretically still have been reached.

Airport manager Rainer Schwarz would not comment on the costs of the delay but Wowereit said the delay would push the airport's financing "to its limits".

Germany's national carrier Lufthansa (LHAG.DE) said it saw other problems besides fire safety.

"We have noticed in test runs over the past days and weeks that there is still need for action on many matters," a Lufthansa spokesman said in a statement.

But the carrier stuck to its plans to expand the number of flights from Berlin and was in talks with Tegel to secure more temporary slots. It plans to increase fourfold the number of non-stop routes to Europe and the Middle East from Berlin.

Germany's second largest carrier, Air Berlin (AB1.DE), said the delay would cause "additional costs which are incalculable at the moment".

The new airport aims to eventually handle up to 45 million people a year. Schoenefeld and Tegel get 24 million, less than half the traffic at Germany's main airport in Frankfurt.

The overnight move from Tegel will require a lot of manpower and mean shutting down a motorway for hours. Airlines have been selling tickets for flights from Berlin-Brandenburg for months.

(Additional reporting by Erik Kirschbaum, Holger Hansen, Maria Sheahan and Peter Maushagen; Edited by Louise Ireland and Stephen Brown)

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