LONDON - Britain may have to accept 1,000 US agents as a part of next year's Olympic security plan due to a serious lack of protection force, the Guardian daily newspaper reported on Monday.

The US has raised repeated concerns about security at the London Olympics, as the London Organizing Committee of the Olympic and Paralympic Games (LOCOG) acknowledged a shortfall of 11,000 in protection force for the games.

Among the 1,000 US agents proposed, 500 of which will be from the Federal Bureau of Investigation (FBI) with a primary mission of protecting American contestants and diplomats, the newspaper reported.

The pressure added by the Americans has caused some concerns over the size of the US "footprint" in the Olympic games next year.

LOCOG had underestimated the number of security guards needed at the 32 venues across the country. Initially it had thought 10,000 guards would be enough, but after a review in the summer it now believes up to 21,000 guards will be needed.

Since venue safety is not among the police's responsibility and the security company hired by the organizing committee is having a hard time put up enough protection force, the Ministry of Defense has offered 3,000 soldiers and another 2,000 in reserve - half the total required - for help.