It is the world’s most expensive embassy, costing more than $700 million (£427 million) and designed to withstand earthquakes and insurgents. Yet only nine months after being opened, the US Embassy in Iraq is riddled with problems expected to cost more than $130 million to fix.

Nobody praised its architecture when it was inaugurated in January — think Milton Keynes on the Moon. The cube-like structure, topped with razor wire, is the size of Vatican City and features a supermarket and swimming pool. But the 2,000 or so Americans moving in believed, at least, that it would keep them safe and comfortable.

Not so. A report by a US Government inspector-general yesterday pointed to staggering State Department incompetence. The structure, measuring more than 100 acres, and supposedly self- sufficient, is facing an enormous repair bill. Plumbing mistakes, for example, mean that the deputy ambassador has sewage-scented air blown into his residence.

A mixing of drains and air- conditioning ducts, writes the inspector, allows “noxious gases to be drawn back into the residence”. In all, 200 places in the embassy suffer similar problems, costing $1.5 million in repairs.

A further $4.6 million will be needed to make the “safe areas” — where diplomats shelter during attacks — actually safe. The strongrooms are, for example, not protected against fire. Another $14 million is needed for “seismic bracing”, specifically requested by engineers but never included in the original building.

During the construction, an American manager suggested that this was “no big deal” but “was unaware that Baghdad was in an earthquake zone”.

The most visible mishaps are on the walls and ceilings. “Buildings are vulnerable to falling plaster debris, especially above doorways and other pedestrian areas,” writes the inspector. “We recommend the plaster be replaced at an estimated cost of $1.1 million.”

There are also problems with the power plant. The chief electrical engineer has restricted it to “60 per cent capacity, because he did not receive information on the performance of each generator.”

The report blames much on the construction company, First Kuwaiti, and suggests that the State Department should seek $132 million in damages. Yet this is hardly the first embassy that America has constructed in a hard place, nor is it the first large US construction project in Iraq.

In the end, the inspector writes, the “underlying error” was the establishment of a construction office “without ensuring they had the necessary personnel, procedures and knowledge to execute the largest project ever undertaken by the Department of State”.

Baghdad residents have little sympathy. “If they can’t build their own embassy, what hope do they have of building a new Iraq,” said Sami Abbas, 44. “At least Saddam’s palaces were always built to perfection, even if nothing else was.”

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