WASHINGTON, Nov 23 - U.S. lawmakers and exiled Chinese dissidents urged U.S. President Barack Obama on Monday to intervene with China's government on behalf of Jiang Tianyong, a rights activist who tried to see Obama while he was in China last week.

The group said Obama should be more outspoken about human rights with the Communist Chinese government. During his visit the American president spoke out for freedom on the Internet and other rights, but avoided sharp jabs in his comments.

Jiang was detained by Chinese authorities after he had gathered with other Chinese rights activists near the U.S. embassy in Beijing last Wednesday, hoping to meet Obama.

Jiang was released. But over the weekend, police surveillance of Jiang's house intensified, Republican Representatives Chris Smith and Frank Wolf told a news conference on Monday in Washington. They said they feared he would be arrested if no appeal is made on his behalf.

"Today we call on you, Mr. President, to personally intervene with your close friend and strategic partner, (Chinese President) Hu Jintao and ask him to cease persecuting Jiang Tianyong," Smith said at a news conference on Capitol Hill.

Wei Jingsheng, a well-known Chinese dissident who was released from jail in 1997 and sent into exile in the United States, said Obama should be more outspoken about human rights by raising cases publicly, not just privately with Chinese officials.

"In talking in private, I do not think that you will have any result," Wei said at the news conference with Smith, Wolf and Harry Wu, another exiled Chinese dissident. "You must put this above the table," Wei said.

Wu appeared with Jiang earlier this month in Washington at a hearing where Jiang testified to U.S. lawmakers about compulsory abortions and sterilizations under China's one-child policy. Jiang then returned to China.

In China, Jiang has defended other Chinese rights activists and volunteered legal aid to Tibetans arrested after demonstrations in 2008. He was one of almost two dozen lawyers whose licenses to practice law were not renewed in May 2009.

Another Chinese dissident who tried to help victims of last year's Sichuan earthquake, Huang Qi, was jailed for three years on Monday on charges of illegally possessing state secrets, his wife said.