Lobsang Sangay, speaking in the exile capital of Dharamshala in India, was marking a day of prayers led by spiritual leader the Dalai Lama to demonstrate the support of Tibetans who have fled their homeland.
The ceremony was "in solidarity with those Tibetans who have sacrificed their lives for the cause of Tibet and particularly those who self-immolated, their families and those suffering repression in Tibet", Sangay said.
"We pay homage to their courage and stand in solidarity with their indomitable spirit," the Harvard academic and international law expert added.
Sangay, who won elections in March, denounced China's "colonialism and systematic destruction of the unique Tibetan culture, religion, language and environment" and criticised the "repressive policies" of Beijing.
China in turn accused the Dalai Lama and his supporters of encouraging the self-immolations of Tibetan Buddhists and said this was "terrorism in disguise".
"In the wake of the incidents, overseas Tibet independent forces and the Dalai group did not criticise the cases," said foreign ministry spokeswoman Jiang Yu.
"On the contrary, they beautified, played up such issues to incite more people to follow suit. As we know, such splittist activities at the cost of human lives is violence and terrorism in disguise."
A Buddhist nun who called for religious freedom as she burned to death this week became the first woman and the ninth Tibetan to set fire to herself in southwest China in recent months, marking a dramatic escalation of the protest.
Self-immolations by Tibetans have until recently been rare and experts say the practice -- condemned in the past by the Dalai Lama -- goes against Buddhist ideas on the sanctity of life.
Hours after the death of the nun Tenzin Wangmo on Monday, two AFP journalists gained rare access to Aba Town, home to the Kirti monastery in southwest China which has become the flashpoint for anti-Beijing protests.
Police in full riot gear carrying automatic rifles and iron bars stood guard outside the huge monastery, one of the most important in Tibetan Buddhism, while all vehicles moving in and out of the town were being checked.
Large groups of soldiers in camouflage and carrying automatic rifles were also spotted amid a large array of police buses, trucks and armoured personnel carriers in the streets.
AFP was unable to gain access to the Kirti monastery, but reporters spoke to monks at a monastery in Hongyuan which neighbours Aba county in southwest China's Sichuan province.
Many blamed China's refusal to engage with the Dalai Lama for the wave of self-immolations and expressed fear that the protests would make their lives even more difficult.
"Tibetans long to see the Dalai Lama. Many people fear that this will not be possible. This is what is causing the problems in Kirti monastery," said one monk at the monastery.
The Dalai Lama fled to India in 1959 following a failed uprising against Chinese rule and is regularly denounced by Beijing.
He began a one-day hunger strike on Wednesday and led the prayer session attended by hundreds of monks and other Tibetans at the main temple in Dharamshala, a northern Indian town in the foothills of the Himalayas.
Also Wednesday in New Delhi, thousands of Tibetan exiles carrying flags and banners marched from Rajghat, a memorial to Indian independence leader Mahatma Gandhi, to a popular protest site in the centre of the capital.
The Dalai Lama's presence in India and the anti-China protests by Tibetans are a constant irritant in the testy relations between Beijing and New Delhi, Asia's two most populous nations.
Sangay said the special prayer session in Dharamshala was held deliberately on a Wednesday in line with a cultural movement called "Lhakar" that is apparently spreading across Tibet.
On every Wednesday, Tibetans in Tibet are making conscious efforts to wear traditional clothes, speak in Tibetan, eat at Tibetan restaurants and do their best to preserve Tibetan culture, he said.