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• Barack Obama tells China to release Liu Xiaobo
BEIJING (AFP) - China said Tuesday that awarding the Nobel Peace Prize to Liu Xiaobo would not influence the country's political system, as the United States urged Beijing to lift restrictions on the activist's wife.
The comments came as Liu's lawyers said they were considering asking for a retrial of the jailed dissident, the co-author of a manifesto calling for bold democratic reforms in the communist state who won the prestigious award Friday.
"Some politicians from other countries are trying to use this opportunity to attack China," foreign ministry spokesman Ma Zhaoxu told reporters, adding the Nobel committee's decision "shows no respect for China's judicial system".
"If some people try to change China's political system in this way and try to stop the Chinese people from moving forward, that is a big mistake," Ma said.
The 54-year-old Liu, a one-time university professor, was jailed in December 2009 for 11 years on subversion charges -- a conviction that sparked international outrage.
The United States, one of many countries that again called for Liu's immediate release following the announcement of the prize, on Tuesday expressed concern about the situation of his wife, who says she is under house arrest.
"We remain concerned by multiple reports that Liu Xia is being confined to her home in Beijing," the spokesman for the US embassy in Beijing, Richard Buangan, said in a statement.
"We continue to follow closely Liu Xia's situation. Her rights should be respected, and she should be allowed to move freely without harassment," he said.
"We urge China to uphold its international human rights obligations and to respect the fundamental freedoms and human rights of all Chinese citizens."
Liu Xia has said via her Twitter account that she has been under house arrest since the Oslo-based Nobel committee honoured her husband, before and after she visited him in prison in the northeast to tell him the news.
Her husband's lawyer Shang Baojun told AFP that she remained under house arrest on Tuesday.
Shang said Liu Xia and the legal team were considering asking for a retrial of the Nobel laureate before a higher court.
"Liu Xia wants to appeal for a retrial. We are still deciding which way to go about it," Shang, who managed to speak to her when he called her brother, told AFP.
"If we do it, of course our defence will be based on a plea of not guilty."
Rights groups and leaders from around the world -- including US President Barack Obama, last year's Nobel peace laureate -- have lauded the choice of Liu as this year's honoree.
China has warned that ties with Norway could suffer as a result. On Monday, Beijing cancelled a meeting scheduled for this week between a Norwegian fisheries minister and a Chinese vice minister.
"By supporting the wrong decision of the Norwegian Nobel Committee, the Norwegian government has moved to hurt bilateral relations," Ma said Tuesday.
Relatives of victims of the bloody suppression of the 1989 Tiananmen democracy protests on Tuesday also joined calls to let Liu walk free.
In an open letter, the Tiananmen Mothers praised Liu for his long struggle to promote democracy and law in China through peaceful, rational and non-violent means, one of the signatories, Zhang Xianling, told AFP.
"We ask the central authorities to immediately release Liu Xiaobo," she said.
"He has fought with and supported the Tiananmen Mothers for over 20 years, he has always stood beside us and today we are standing by him."
Liu helped negotiate the safe exit from Tiananmen Square of thousands of student demonstrators before tanks crushed the six weeks of peaceful protests in the heart of Beijing on June 3-4, 1989.
He was previously jailed for his involvement in the Tiananmen movement.
The US-based group Human Rights in China quoted Liu as telling his wife over the weekend that he had dedicated the award to "the lost souls of June Fourth".