But department officials allowed that Russia's concerns about the bombing, delivered in urgent diplomatic demarches late Tuesday, were unlikely to have been assuaged.

"They're really worried we're going to do a China number on their embassy," said one senior official, referring to the mistaken NATO bombing of the Chinese embassy in Belgrade during the 1999 Kosovo crisis.

"All we can tell them is that we aren't targetting them and we'll do our best," the official told AFP on condition of anonymity. "We can't really tell if they're satisfied with that."

The Russian foreign ministry said earlier Wednesday that it had delivered a formal protest to US ambassador to Russia, Alexander Vershbow, after US bombs fell near the Russian embassy in Baghdad, endangering its diplomats there.

"Several bombs fell on a civilian district of Baghdad where the Russian embassy is located," it said in a statement. "The lives of Russian diplomats were placed in immediate danger."

Russia has withdrawn its non-essential diplomatic personnel from Iraq but has kept its Baghdad embassy open with a skeleton staff.

Lynn Cassel, a State Department spokeswoman, confirmed that the complaint had been delivered to Vershbow and the US diplomats in Washington by Russian ambassador to the United States Yury Ushakov.

"Russian authorities have expressed their concern ... over what they allege is the heavy bombing by coalition forces of the area of Baghdad surrounding the Russian embassy," she said.

"We have relayed these concerns to the appropriate US military authorities and have reassured Russian authorities that US military forces are using precision weapons and are taking great care to avoid any unnecessary damage to non-military sites, including embassies," Cassel said.

A second department official who spoke on condition of anonymity said there was no evidence that any bombs had falled closer than 600 meters (yards) from the Russian embassy and hinted that Moscow was overplaying the danger.

"Sure, the building is going to shake a little, but it's not going to be hit," the official said. "We know where it is."

In 1999, NATO bombed the Chinese embassy in Belgrade, killing three people, in an accident that was blamed on the use of an out-of-date map of the city.

China reacted furiously and some Chinese still believe that the strike was intentional.

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