Reports have suggested that the USA could send up to 1,000 of its own agents, including 500 from the FBI, to look after America’s contestants and diplomats at London 2012.
The restriction of the scope of anti-terrorism stop-and-search powers is claimed to be one of their reasons for concern.
National Olympic security co-ordinator Chris Allison, of the Metropolitan Police, said he believes Britain has everything needed to police the Games properly.
“The Games is a massive challenge, we mustn’t underestimate that, but I’m satisfied that we’ve got the skills and the expertise to make sure that they pass off and the focus is on what they should be, a fantastic sporting spectacle,” Allison told Sky News.
“I’ve been involved in Games planning since 2008 and whilst I’m not complacent and recognise there’s still quite a bit to do, I think we’re in a very good place at the current time.”
Asked whether the force had 12,000 officers to spare for the Games he said there would be 12,000 on peak days and about 9,000 of them in London, with officers from up and down the country helping out in a “joined-up policing and security operation”.
Along with the police force, another 10,000 to 15,000 security officials could also be deployed by firm G4S. The Ministry of Defence is also understood to be involved in security discussions.
A Home Office spokesman said: “Security planning is on track and funding has been protected. The Government is committed to delivering a safe and secure Games that London, the UK and the world can enjoy.
“The International Olympic Committee (IOC) undertake detailed inspections of security preparations and have full confidence in our plans. The UK has a strong and close working relationship with the US, who have expressed similar confidence.
“The Government, London 2012 Organising Committee (LOCOG) and G4S are working together to finalise the requirement for venue security and, as is common at major events in the UK, we will make the best and most appropriate use of all available resources.”
A Home Office source said it did “not recognise as true” suggestions there are concerns from the US. The US state department declined to comment, and the FBI was not available for comment.
London 2012 said the venues and competition schedule needed to be completed before they could finalise security plans.
A statement from the organising committee said: “Since winning the bid, a huge amount of collaborative work has been completed.
“We finalised the competition schedule, with 650 sporting sessions over 18 days, built and selected over 100 competition and non-competition venues, and designed the transport and accommodation plans.
“This all needed to be in place before the detailed security plans could be confirmed.
“Over the last year LOCOG has been working in close collaboration with government and the security agencies, whose role it is to determine all risk and mitigation aspects of security for the Games.”