London 2012: US guards 'will not be armed at Games'
Olympics organisers have strongly denied reports that armed US security officers would be used at London 2012.
Locog CEO Paul Deighton rejected a story in The Guardian claiming the US was furious about security plans and wanted to send 1,000 of its own guards.
"What was reported yesterday has no basis and the Americans themselves have rejected it," said Mr Deighton.
He was answering questions from a panel of MPs on the Culture, Media and Sport Committee.
The US embassy in London had earlier also denied the story, saying it had the "utmost confidence" in the British government's arrangements to ensure safety and security for the Olympic Games.
In a letter to the Guardian, the embassy's Charge d'Affaires Barbara Stephenson said it was "normal and prudent for the US to engage in discussions".
"[The Americans] are very happy with what we are doing and it is highly collaborative," Mr Deighton told the MPs.
He added that more than 20,000 security personnel would be needed at peak times. Volunteers would be used as well as staff from the security firm G4S - which is contracted to guard Games venues - and the British military to meet the requirements of more than 10 million hours of "man guarding", he said.
The option of using UK troops was attractive because soldiers were "pre-trained and highly respected", said Mr Deighton.
The Home Office said on Monday it had "full confidence" in Games organisers' security plans, with a spokesman adding that the International Olympic Committee (IOC) - which undertakes detailed inspections of security preparations - felt the same.
But Defence Secretary Philip Hammond had earlier told MPs that ground-to-air missiles would be deployed to protect Olympic venues if deemed operationally necessary. The level of security threat is set to be at severe throughout the Games.
The deployment of overseas security officers at the Olympics has become standard procedure in recent years but final responsibility for security rests with the host government.
National Olympic security co-ordinator Chris Allison said on Monday there would be a small number of "foreign security liaison officers" in London to act as a link between their national teams and UK police. But he insisted their numbers would not be on the scale reported.
The US was providing "great support", Mr Allison added, and their officials did not "recognise" the concerns expressed in The Guardian report.
It said London August riots, the arrest of a security guard at the Olympic site and arrests before the visit of the Pope last year had raised US anxieties, while the restriction of the scope of anti-terrorism stop-and-search powers was also claimed to have caused concerns.
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Responding to claims in the article, Locog said precise numbers of security officers were only now being finalised because the venues themselves had only just been completed.
Earlier this year Mr Allison said 12,000 officers may be needed nationally to police the event and another 10,000-15,000 security officials could also be deployed by G4S.