Protesters briefly disrupted the event as China?s representative spoke, evading some of the 1,000 police officers in Olympia. Pro-Tibet activists had vowed to protest over the violence in Tibet.

The torch is to be carried through 20 countries. It will pass over Mount Everest and into Tibet, before arriving in Beijing for the Games on 8 August. As Liu Qi, head of the Beijing Olympic organizing committee, spoke ahead of the torch lighting, a man ran up behind him attempting to display a flag.

He was quickly bundled away by police and Mr Liu continued his speech uninterrupted. The camera cut away from Mr Liu and the protester until he had been removed from the scene.

Actors dressed in ancient Greek costume then lit the torch in the traditional manner by using a parabolic mirror to focus the sun?s rays. There were fears that stormy weather would prevent the torch being lit in the customary way. The ceremony, beside the Temple of Hera, was moved forward by an hour and the sun shone through a break in the clouds.

Free access for all media

The head of the International Olympic Committee (IOC) has defended the decision to hold the Games in China saying there was ?no momentum? for a boycott.

?The major political leaders don?t want a boycott,? said IOC president Jacques Rogge, ahead of Monday?s ceremony. Before the ceremony, a Tibetan activist confronted Mr Rogge in a hotel lobby and said there should be free access for all media inside China, including Tibet, during the Games.

In his speech during the ceremony, Mr Rogge said the Olympic torch relay and the Games should take place in a peaceful environment. ?The torch is the link between all athletes and citizens of this world; between all of us who believe in Olympism and the virtue of sport. It has the force to unite humanity and to stand for harmony.? He has previously said that holding the games in Beijing will hold China up to scrutiny and potentially prompt change.

Anti-China protests began in Tibet?s main city, Lhasa, on 10 March and gradually escalated. Lhasa saw at least two days of violence and there have also been violent protests in provinces which border Tibet.

China says 19 people were killed by rioters and accuses Tibetan spiritual leader ,the Dalai Lama, of inciting the violence. The Tibetan government-in-exile says at least 99 people have died in a crackdown by Chinese troops and deny any role in organizing the protests.