Police bundled protesters wearing yellow "Free Tibet" t-shirts into buses in the diplomatic quarter of the Indian capital, an AFP reporter witnessed.

In Nepal, police have also warned Tibetan exiles not to organise demonstrations to coincide with the anniversary of the failed uprising against Chinese rule in Tibet.

"We can not tolerate any activities against our northern neighbour. Nepal police will stand by the state policy not to allow anti-China activities on its soil," Kathmandu police chief Pushkar Karki told AFP.

New Delhi is sensitive to anti-China demonstrations from the Tibetan community in exile, many of whom have lived in India since the country offered refuge to spiritual leader the Dalai Lama in 1959.

The Dalai Lama fled over the Himalayas into India amid a brutal Chinese crackdown on protests against rule from Beijing.

The 75-year-old Tibetan spiritual leader is to deliver a speech on Thursday at the Tsuglakhang Temple in Dharamshala, the Indian hill town that is his base and the seat of the Tibetan government in exile.

Many Tibetans complain about the increasing domination of China's majority Han population in Tibet and accuse the government of trying to dilute their culture.

Chinese authorities have closed the troubled region to foreign tourists ahead of the third anniversary of the anti-government riots.