China accused the Dalai Lama on Tuesday of orchestrating Tibetan riots to wreck Beijing's Olympic Games, but the exiled spiritual leader denied the charge and vowed to stand down if the violence spiralled out of control.

The Tibetan government-in-exile said from the Dalai Lama's base in the Indian Himalayan foothills that it now believed 99 people had died in clashes between Chinese authorities and Tibetan over the past week, including 19 on Tuesday alone.

Premier Wen Jiabao defended the security crackdown on Lhasa, capital of the predominantly Buddhist Himalayan region, and on neighbouring Chinese provinces where copycat rioting by Tibetans erupted over the weekend.

"There is ample fact and plenty of evidence proving this incident was organised, premeditated, masterminded and incited by the Dalai clique," Wen told a news conference in Beijing.

"This has all the more revealed the consistent claims by the Dalai clique that they pursue not independence but peaceful dialogue are nothing but lies."

A Chinese Foreign Ministry spokesman later went as far as saying that the Dalai Lama, who fled Tibet in 1959 after a failed uprising against Chinese rule, should face trial.

The Dalai Lama denied the charges laid against him and said he would resign as Tibetan leader if the violence got out of hand.

"If things become out of control then my only option is to completely resign," the Nobel peace laureate told a news conference in Dharamsala, northern India.

Tenzin Taklha, a spokesman for the Dalai Lama, said the rioting started with one or two incidents. "Because of technology, because of word of mouth, word quickly spread," he said. "This was very spontaneous."

The Dalai Lama consistently says he is not seeking independence for Tibet and instead wants autonomy within China, which sent troops into the region in 1950.

"NO CALLS FOR BOYCOTT"

Several days of monk-led anti-China protests in Lhasa, the biggest in almost two decades, turned ugly last Friday, weighing uncomfortably on the Communist leadership anxious to polish its image in the build-up to the Olympic Games.

An exiled Tibetan rights group said on Tuesday that 30 Tibetan protesters were arrested after staging a demonstration near Lhasa.

A dozen Buddhist monks from the Dinka Monastery in Duilong Deqing County (Toelung Dechen in Tibetan) near Lhasa, held the protest on Monday evening and were joined by local lay residents, the Tibetan Centre for Human Rights and Democracy said on its Web site (www.tchrd.org), citing "numerous sources and witnesses".

Reuters was unable to immediately confirm the report. Foreign media are barred from travelling to Tibet without permission.

Chinese authorities have said that security forces exercised restraint in response to the Lhasa burning and looting, using only non-lethal weapons, and only 13 "innocent civilians" died.

Wen said the protesters "wanted to incite the sabotage of the Olympic Games in order to achieve their unspeakable goal".

Western nations have called on Beijing to exercise restraint, but International Olympic Committee President Jacques Rogge told Reuters in Trinidad on Monday that there had been "absolutely no calls" from governments for a Beijing Games boycott.

In Taiwan, which China considers its own, presidential candidate Ma Ying-jeou of the opposition Nationalists, who have traditionally favoured better ties with China, said on Tuesday he would consider an Olympic boycott if elected on Saturday.

"If the Chinese Communists continue to suppress the Tibetan people and the situation in Tibet continues to worsen and if I am elected president, I would not rule out not sending a team to the 2008 Beijing Olympics," Ma told reporters.

Foreign policy analyst Tony Kevin at the Australian National University said the muted international reaction to the crackdown was expected, given China's economic and strategic importance.

"China ... is subjected to different standards of human rights than less important countries," he told Reuters.