Commissioner Raymond Kelly said London's police and security planning was far more comprehensive and organised than had been the case for the Atlanta games in 1996 in which he was personally involved in a federal government role.

"It seems they really have a handle on just about any contingency that might take place," Kelly told Reuters in London during a trip to meet Olympic security chiefs, senior London police and officials at Britain's MI5 domestic security agency.

"We've been universally very much impressed with everything we've seen. As far as I can see they have done an excellent job preparing all of their forces."

Last November, the United States denied that there had been a diplomatic row over the Olympic security planning, following a newspaper claim that 1,000 agents including some 500 from the FBI, would be sent to protect U.S. athletes and officials.

Chris Allison, Britain's national Olympic security coordinator, said the claim was rubbish and that the reported FBI contingent had been grossly exaggerated.

"I think the FBI role is a supportive one. I don't think they're here with specific concerns," Kelly said, dismissing the idea that the London police needed their assistance.

He added than rather than lecturing the British, his visit had been a learning one.

"We were takers rather than givers, put it that way," he commented.

Allison and other senior British security figures have said protests and public order issues rather than al Qaeda and international terrorism were the most likely threats to the Games.

Last year, Britain suffered its worst rioting in decades and there have been high-profile anti-capitalist protests in London, some inspired by New York's Occupy Wall Street moment.

Kelly said he had discussed the riots with his London counterparts and it was an issue that they had factored in, with plans for a rapid mobilisation to deal with any unexpected events.

"Will there be demonstrations, will there be protests of some sort? Sure. That's a given in this day and age. It's something that happens in New York and London literally everyday," Kelly said.

"But the Met (London Metropolitan Police) is well experienced. They're well prepared to handle it."

(Editing by Justin Palmer)

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