For decades the United States could not conceal its glee that it owned the prime piece of real estate in Germany, the precious space adjoining the Brandenburg Gate, the symbol of a united Europe. It may now be having second thoughts.

Germany's architectural critics were queueing up yesterday to savage the new, squat, custard-coloured US Embassy, built on one of the country's most historically and emotionally charged parcels of land.

“There is hardly a modern building in existence - with the exception of nuclear bunkers and pesticide-testing centres - that is so hysterically closed off from public space as this embassy,” the conservative Frankfurter Allgemeine Zeitung said. “Of course an embassy needs security features - but the French, the British and the Italians manage to achieve this without giving the observer the impression that he is entering the green zone in Baghdad.”

The competition to design the embassy was won in 1995 by the Santa Monica-based partnership Moore Ruble Yudell. Since then, security restrictions have become the key consideration in embassy design: US embassies in Kenya and Tanzania were the targets of suicide bombers in 1998.

The city of Berlin refused the architects permission to construct a 30m security zone, since this would have sliced up Pariser Platz, the square that links the Brandenburg Gate to Unter den Linden, Berlin's most famous boulevard. As a result much of the security - including its bomb-proof, reinforced-steel walls - has been compressed into a very cramped, labyrinthine building.

The Süddeutsche Zeitung critic called it “Fort Knox at the Brandenburg Gate”, while the Berliner Zeitung said it was a “maximum-security prison made to withstand exploding trucks and rocket fire”. Another critic complained: “If a building could stand with its arms crossed, it would look like this one.”

The Fankfurter Aallgemeine Zeitung put the boot in: “The American Embassy - with its cheap materials, its narrow arrow-slit windows, its defensive tower - looks as if it was planned for another, more unsettled part of the world.”

The embassy will be opened formally on July 4 by the former President George H. W. Bush, but nobody wanted to comment yesterday as diplomats filed into work for the first time.

Ordinary Germans were more charitable about the design. Bernd Hofer, a teacher from Karlsruhe, who was taking a school trip to the Brandenburg Gate, conceded: “Well, yes, I suppose it is ugly, but the thing about ugly buildings is you don't really notice them. Not in Germany at least.” Other passers-by showed understanding for the safety of US staff: “You don't want it exploding, do you?”

It is the misfortune of the Bush Administration that this is the first big US embassy building to be opened since the September 11 attacks. The British Embassy in Berlin, around the corner in Wilhelmstrasse, is much more open in its design and boasts a huge atrium for entertainment - though it, too, has steel protection gates and is heavily policed.

Perhaps the ultimate ignominy is the verdict that the new embassy - “as elegant as a council house” in the words of one critic - is letting the area down. It is a short stroll from the most important cultural landmarks in the German capital: Humboldt University, Karl Friedrich Schinkel's 18thcentury guard house, the Staatsoper opera house and two Baroque palaces.

Above all, the embassy demeans the Brandenburg Gate, which creaks with history: Napoleon marched through it in 1806, revolutionaries met there in 1848 and 1918 and the Nazis used it for torch-lit rallies. When Berlin was divided during the Cold War, the Gate was in the eastern side of the Berlin Wall but visible to Westerners, symbolic of the yearning for German unification.

The Americans could be forgiven for thinking that the plot of land is jinxed. They bought the palace that once stood there in 1930 with a view to turning it into an embassy, but the opening was delayed by a fire and by the time the diplomatic offices were ready the Nazis had come to power. The US recalled its ambassador. During the Second World War the building was bombed, and the East Germans cleared away the ruins and left it as scrubland.

The FAZ critic added: “This embassy represents a country that has been traumatised by 9/11 and the consequences of globalisation - a nation which is so protected by armour that it can no longer see the world.”

The new building meanwhile has been dogged by conflict between Washington and the city government of Berlin. The Germans, it is clear, are uneasy about the prominent positioning of the United States so close to their iconic Gate. The Americans, judging by the body language of US diplomats entering the building yesterday, are not particularly enthusiastic either.

“If a building could stand with its arms crossed, it would look like this one,” one critic wrote. “Perhaps it is also typical of the first decade of the 21st century that public space, which once looked like a promise, is now perceived as a threat.”

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