The Chinese government is holding a ceremony marking 50 years since it established Tibet as an ethnic autonomous region.

Top political adviser Yu Zhengsheng stressed that Tibet was ethnically united during a speech in the Tibetan capital of Llasa in front of the Potala Palace, once home to the Dalai Lama and now a museum.

Yu said the Himalayan region had gone through many changes during the 50 years, and its gross domestic product had grown 68 times.

He mentioned the Dalai Lama, the Tibetans' spiritual leader, who Beijing regards as a separatist. Yu said that activities by him and others to "split China and undermine ethnic unity have been defeated time and time again."

London-based Free Tibet said Beijing was trying to define Tibetan identity according to its priorities.