This new condition, which has been added to existing ones for the exiled Tibetan spiritual leader to give up his demands for independence, emerged during a telephone conversation with US President George W. Bush late on Wednesday night.

Analysts said the remarks reflected growing anxiety in Beijing about the fallout from the Tibet issue, which has not only ignited riots in Tibetan towns in remote western China, but also triggered growing talk of an Olympics boycott in August.

Czech President Vaclav Klaus and Polish Prime Minister Donald Tusk have announced that they will not attend the Beijing Games due to the Chinese government's handling of the unrest in Tibet.

French President Nicolas Sarkozy, who has not ruled out a boycott, said yesterday he would ask other European Union leaders whether they want a boycott of the Olympics opening ceremony.

But there are doubts as to whether the Dalai Lama alone can cool simmering tensions, which boiled over on March 14 when riots broke out in Lhasa, Tibet's capital, in western China.

'I don't think all of the Dalai Lama's followers will listen,' said Mr Wang Lixiong, a leading expert on Tibet. 'There is also the question of Beijing's sincerity.'

Mr Hu is seen as the most critical voice in the Chinese leadership for resolving the Tibet issue, given that he was the restive region's top leader in the 1980s and was the one who crushed the last major rebellion there in 1989.

But he mostly steered clear of tough talk when he spoke to Mr Bush, who has pledged to attend the Beijing Games and who has said that politics should not interfere with athletic competition.

When Mr Bush urged Beijing to hold 'substantive dialogue' with the Dalai Lama's representatives, the Chinese leader responded by saying that Beijing had exercised 'great patience' in its contact with the Dalai Lama over the years, the official Xinhua news agency reported.

Mr Hu added that the Chinese government was prepared to hold talks as long as the Dalai Lama renounced his push for Tibetan independence and stopped 'activities aimed at splitting the motherland, especially activities to fan and mastermind violent crimes in Tibet as well as in some other regions and to sabotage the upcoming Beijing Olympic Games'.

Though he described the recent rioting in Tibet as 'undisguised serious and violent crimes', Mr Hu avoided making the fierce personal attacks that have come to characterise Beijing's recent rhetoric against the Dalai Lama.

'No responsible government would sit by and watch when faced with this kind of violent crime, which gravely violated human rights, seriously disrupted social order, and seriously endangered the safety of public life and property,' Mr Hu said.

Previously, Beijing had described the unrest in Tibet as 'organised and planned violent crimes plotted and incited by the Dalai clique'.

The Dalai Lama did not respond directly to Mr Hu's comments yesterday, though the Tibetan leader had previously said that he only wanted autonomy for Tibet.

He had also criticised the recent violent rioting and said he did not support calls for an Olympics boycott.

chinhon@sph.com.sg