Vice-President Xi Jinping told yesterday's gathering: 'The modern Olympics is an event meant for peace and friendship.

'We hope the Olympic torch relay will bring people together around the world, to realise the ideal of one world, one dream.'

It was Mr Xi's first public speech since being named as the Communist Party's top point man to handle Olympic-related affairs.

In the Laotian capital Vientiane, Premier Wen Jiabao echoed Mr Xi's call for world solidarity in China's efforts to stage a grand Olympics, although he admitted things could go awry.

'We hope things will go smoothly with the torch relay but it may be inevitable that some interference will happen,' Mr Wen said on the sidelines of the Greater Mekong Subregion summit.

'But we have the confidence in having the full support and goodwill of people and governments around the world.'

Mr Hu did not deliver a full-length speech in Tiananmen but set up the highlight of the ceremony by passing the flame to Olympic and world champion hurdler Liu Xiang, the nation's most acclaimed athletics hero.

To loud cheers from the crowd, Liu jogged off the podium after standing alongside the president with the torch.

Behind them was a deserted Changan Avenue, the capital's main thoroughfare, which was closed to traffic for most of the morning, including the rush hour.

Proceedings at the one-hour ceremony were watched over by hundreds of paramilitary, police and plain-clothes officers scattered throughout the vast square. Most of the audience, including some 200 media representatives, were asked to check in three hours before the ceremony, and were ushered through airport-style security checks.

The torch's 137,000km trek includes stops in 134 cities in 21 countries. It was lit in Olympia, Greece, on March 24.

The torch is scheduled to leave Beijing for Almaty in Kazakhstan today on the first leg of a 19-city overseas tour.

The flame will return to China early next month where it will go on a three-month domestic tour, starting in Hong Kong on May 2, before the cauldron at the Games' main centrepiece, the National Stadium, is lit during the opening ceremony on August 8.

Given the protests in Olympia at the torch-lighting ceremony last week, there were fears yesterday of possible demonstrations by protesters with grievances over various issues, ranging from Beijing's crackdown on recent rioting in Tibet to its dubious human rights record.