London 2012 chief Seb Coe has insisted that the security of the Olympics has not been compromised despite the failure of G4S to provide enough staff.

The security firm was contracted to provide 10,000 staff for the Games but fell well short – leading to 3,500 army personnel to be drafted in only a few weeks before the opening ceremony.

But Coe told BBC Radio 5 live: ‘We will work very hard, we will remedy this – security will not be compromised.’

He added: ‘This is not about numbers, this is about the mix. I can’t put it more simply than this, G4S expected people to materialise and when they didn’t, as the home secretary has said, we moved very quickly to fill that gap.’

Coe insisted that G4S would continue to play a central role in Olympic security.

‘I’m in the Olympic Park every day – we’ve got 4,000 trained G4S personnel in the park and they’ve been there for some years and they’ve been doing a spectacularly good job.’

Coe said it was ‘absolutely not for me to even speculate on’ whether G4S chief executive Nick Buckles should quit over the furore.

Buckles said he only became aware of the problem ‘eight or nine days ago’ but reports suggest potential problems were flagged up to the Home Office 10 months ago.

G4S has revealed it stands to lose up to £50m on its Olympic contract due to the staff shortage.