Troops from Suffolk will be drafted in to shore up Olympic security after G4S admitted it could not provide enough staff in time for next week's opening ceremony.

2 Squadron RAF Regiment, based at RAF Honington, whose return from Helmand Province, Afghanistan was only celebrated at the end of June, will now report for duty at London 2012 sites.

An RAF Honington spokesman said the regiment had already been on standby and any 'changes to readiness' would have a 'minimised impact on personnel'.

All leave affected by the security work at the Olympics will be rearranged.

The spokesman said: '2 Squadron is proud to play its part in ensuring a secure, enjoyable Olympics for all. This task is a reminder that the squadron is as important a part of the UK's armed forces today as it has been for the past 90 years. 2 Squadron was not committed to any ongoing operation at this time and was fully prepared to assist with Olympic security if required.'

He added: 'To ensure a safe and secure Games, the armed forces have been asked to supplement the civilian venue security force.

'Every recent Olympic Games has had a significant military presence, so using armed forces to assist with security is not a new concept.'

The announcement by RAF Honington that 2 Squadron will be sent to London comes as the Ministry of Defence (MoD) make preparations to call upon between 500 and 2,000 additional troops if G4S fails to to deliver on its revised target of 7,000 staff.

Nick Buckles, G4S chief executive, told a Commons home affairs select committee on Tuesday that the episode had been an 'humiliating shambles' and admitted he could not predict the number of 'no-shows' from recruits.

The Home Secretary, Theresa May, who last Wednesday authorised the call-up of 3,500 extra troops to bail out the private security company, has not made any further official request for troops and is working to avoid exactly that situation.

An MoD spokesman said: 'As the defence secretary made clear at the weekend, should there be a requirement for additional military personnel the MoD will do whatever possible to make them available.

'At the present time no further requests have been received but, as people would expect, an ongoing programme of prudent planning continues.'