(Adds Dalai Lama statement; paragraphs 6-9)
By Benjamin Kang Lim and David Stanway
BEIJING, March 30 (Reuters) - Phuntso Wangye, a veteran Tibetan Communist leader who became an outspoken critic of Beijing's hardline policies towards the Himalayan region, died on Sunday, his son said. He was 91.
"He left this morning," Phuntso's son, Phunkham, told Reuters by telephone. "Before his death, he was a Communist Party member. After his death, we have invited lamas to pray (for his soul) according to traditional Tibetan culture."
Phuntso, who had been in hospital in Beijing since July, had recently developed lung problems.
Born in 1922 in the Tibetan county of Batang, now part of China's province of Sichuan, Phuntso founded the Tibetan Communist Party and launched a series of guerrilla uprisings against Nationalist Chinese rule until joining forces with the Chinese Communist Party in 1949.
He led troops of China's People's Liberation Army into the remote mountain region in 1951 and served as translator for Chinese leaders Mao Zedong and Zhou Enlai during talks with the Dalai Lama in 1954. Phuntso was later purged and spent 18 years in solitary confinement before being rehabilitated in 1978.
Phuntso had showed that one "could be a true Communist" while at the same time taking pride in his Tibetan heritage, the Dalai Lama said in a statement on Sunday, adding that he was deeply saddened by the news.
"Despite his firm upholding of Communist ideals, the Chinese authorities regarded Phuntsog Wangyal's dedication to his Tibetan identity in a negative light, as a result of which he spent 18 years in prison," the Dalai Lama said.
"He remained undaunted and even after his retirement continued to be concerned about the rights and welfare of the Tibetan people, something he raised with the Chinese leadership whenever he had the opportunity."
Tibetans' names have numerous variations when spelt in English.
His biographer, Melvyn Goldstein, quoted Phuntso as saying that while he experienced hardships "beyond description" during his years at the notorious Qingchen Prison, they saved him from an even worse fate during what he called China's "chaotic" Cultural Revolution.
Later, Phuntso turned down the chance to be chairman of the Tibet regional government, and became increasingly critical of Beijing's position on Tibet and the Dalai Lama, who fled into exile in India in 1959 after an abortive uprising against communist rule.
LETTERS TO THE PRESIDENT
Phuntso wrote several letters to then-President Hu Jintao condemning leaders in Tibet for using a campaign against "splittism" to serve their own political ambitions and for refusing to acknowledge the Dalai Lama's role in Tibetan society.
He also urged Hu to let the Dalai Lama return home, saying this would help make the region stable.
Phuntso's death "brings huge regrets", dissident Tibetan writer Woeser told Reuters by telephone.
Phuntso continued to urge China's leaders, including President Xi Jinping, to reconsider their stance on Tibet, she said. "He had hoped the Chinese leadership could hold talks with the Dalai Lama and let the Dalai Lama return to Tibet."
Phuntso's death silences one of the voices sympathetic to the Dalai Lama" in the Communist Party, said Wang Lixiong, author of several books on Tibet. (Additional reporting by Sui-Lee Wee, Editing by Richard Borsuk and Clarence Fernandez)