A senior Tibetan official has left China and is reported to have gone into exile in the United States.

The official, Arjia Rinpoche, is one of the most senior Tibetans to have left the country since the Dalai Lama went into exile in 1959.

He was the abbot of one of Tibetan Buddhism's most important monasteries, and also held high-ranking positions in the Chinese hierarchy.

A source in the Tibetan government-in-exile in India told the BBC that the abbot left Tibet around four months ago, following disagreements over China's religious policies.

The BBC correspondent in Beijing says the incident is likely to be a considerable embarrassment for the Chinese government.