Chinese police barred prominent dissident Hu Jia from leaving home Monday after he proposed marking UN Human Rights Day near the home of a jailed Nobel laureate's wife, who is herself under house arrest.

Authorities have detained Liu Xia at home without charge since her husband Liu Xiaobo -- the co-author of a human rights petition -- won the 2010 peace prize. He was convicted in 2009 of inciting subversion and sentenced to 11 years in jail.

December 10 marks the day the Charter 08 petition was signed and the day Liu should have received his Nobel award.

Hu had posted a note on Twitter on Friday suggesting that a park near Liu Xia's home would "be a good place to hold a human rights press conference" to mark the date.

But on Monday he told AFP: "The police are keeping me in my home until Tuesday to prevent me from meeting with people like you so that I will not be photographed or filmed for Human Rights Day."

Hu served three years in jail starting in 2008 after years of campaigning for civil rights, the environment and AIDS patients, and has remained under surveillance since being released.

Liu is one of three people to have won the Nobel award while jailed by their government, and his imprisonment elicited international condemnation.

China strongly condemned his Nobel prize as unwanted foreign interference in its internal affairs, and refused to allow him to attend the ceremony in Oslo -- where he was represented instead by an empty chair.

The European Union is due to be presented with the 2012 peace prize later Monday, and in a statement to mark Human Rights Day, EU Special Representative for Human Rights Stavros Lambrinidis called Liu's sentence a "clear violation of his right to freedom of expression".

His wife has been held under house arrest since the award was announced. The government has refused to specify the charges against her or explain why she has been detained.

US-based advocacy group the Southern Mongolian Human Rights Information Center on Monday published letters it said were written by family members of Hada, an ethnic Mongol dissident who has completed a 15-year prison term but not been released.

In December 2010 Hada, who like many Mongolians goes by a single name, finished his sentence for espionage and separatism after he advocated greater political rights for China's six million Mongols.

"Detaining Hada after the completion of his full prison term is an illegal act," Hada's wife Xinna wrote to the head of the local police force, adding that neither she nor her son had been allowed to visit him.

"Life has been extremely difficult for us both... over these years. One can walk out of the debris of history, but one cannot come out of the dark shadow of persecution," the letter said.

China has repeatedly dismissed criticisms of its human rights record, with a government spokesman saying earlier this year that China is committed to "promoting Chinese citizens' rights in accordance with the law".