The opening of Berlin's new airport on Oct. 31 will happen without fanfare, operators say, a nod to the long delays and massive cost overrun since construction started in 2006.

Airport boss Engelbert Luetke Daldrup conceded Tuesday that the repeated postponement from the once-promised opening date in 2011, blamed on construction and technical problems, had made Berlin and Germany "a laughing stock."

"We German engineers were ashamed," he told reporters in the capital.

The costs, which shot up from an original budget of 2.7 billion euros to almost 6 billion euros ($7 billion), were "not acceptable," Luetke Daldrup acknowledged.

As such, the opening will be low key, he said. "There will be no big party. We’re simply going to open."

The Berlin Brandenburg Airport, also known simply as BER, will replace the city's two small Cold War-era airports, Schoenefeld and Tegel. The former will be used as a third terminal for the adjacent new airport, while the latter will be closed for good after 60 years of service.

Tegel, which was located in the French-controlled sector of West Berlin when it opened in 1960, will receive a send-off before it finally closes on Nov. 8, said Luetke Daldrup. The final departure will be an Air France flight to Paris.

The new airport will be Germany's third-biggest in terms of passenger numbers, behind Frankfurt and Munich.

Luetke Daldrup said operators fear the coronavirus pandemic might mean that the record number of 36 million passengers seen by the existing two airports last year isn't achieved again until 2024.

He called for more long-haul slots for the new airport to ensure passengers from Asia and the Middle East can fly directly to Berlin.