The security company G4S has been at the center of a political firestorm, since it announced it could not provide the promised number of Olympic security guards just two weeks before the Games.

The head of the company has admitted that his mismanagement has embarrassed the British government and left the world’s biggest security firm's reputation in tatters.

He leads the company which has admitted it can't provide the 10,000 Olympic security staff it promised.

G4S Chief Executive Nick Buckles speaks during a hearing with the parliamentary committee in London in this still image taken from video July 17, 2012.

At a UK parliamentary committee, G4S Chief Executive Nick Buckles came face to face with MPs demanding to know why.

Question: Mr. Buckles, it's a humiliating shambles isn't it?

Buckles: It's certainly not where we want to be.

Question: It's a humiliating shambles for the company, isn't it?

Buckles: I cannot disagree with you.

Buckles was asked why he was still in his post after his company failed to reveal until the start of July that they didn't have enough guards, only weeks before the start of the games.

Buckles says, "It's not about me it's about delivering the contract. Secondly, I feel I am the right person at the moment to do that and make sure it happens, and make sure our company comes out of this with its reputation in tact. My future is my third concern and not my current concern."

To make up the shortfall left by G4S not fulfilling its contract, 3 and a half thousand extra troops have been drafted in, some only just returning from the war in Afghanistan.

Police from around the UK will also help.

Buckles also says, "To get 10,000 people on the ground in a relatively short period of time has been a huge logistical challenge. We did not know that the contract was not going to perform until very late on purely because the whole process is very back ended in terms of getting everybody ready for the games."

The failure to deliver the security guards looks set to cost G4S up to 50 million pounds, and its value has already slumped by nine percent.

The saga has ignited a bigger political storm in the UK with the government facing difficult questions over its outsourcing of key security work.