Mo Yan, seen as being close to Communist party, says he wishes peace prize-winner Liu Xiaobo achieves freedom soon

The Chinese Nobel literature prize-winner, Mo Yan, has unexpectedly expressed hope for the release of jailed dissident Liu Xiaobo, who won the 2010 peace prize to the fury of Chinese authorities.

Speaking hours after the judges announced his award, the novelist said: "I hope he [Liu] can achieve his freedom as soon as possible." Liu should be able to research his "politics and social system", Mo added.

Mo has been feted in China, with the country's propaganda chief, Li Changchun, praising him and newspapers plastering his image across their front pages, in stark contrast to the authorities' wrath at Liu's win.

The novelist had previously declined to comment on Liu, and several activists and dissidents reacted angrily to his honouring because they felt he was too close to the authorities. "The people who have criticised me have not read my books," Mo told reporters in his home town of Gaomi in Shandong. "If they had read my books they would understand that my writings at that time took on a great deal of risk and were under pressure.

"Many of the people who have criticised me online are Communist party members themselves. They also work within the system. And some have benefited tremendously within the system," he added, according to Reuters.

"I am writing in a China under Communist party leaders. But my works cannot be restricted by political parties."

Mo said he had read some of Liu's literary criticism in the 1980s, but had no understanding of the former academic's work since its turn towards politics.

Liu, a writer and critic, is serving 11 years for incitement to subvert state power as co-author of Charter 08, a document calling for democratic reforms in China.

His wife, Liu Xia, is believed to be under house arrest in Beijing, as she has been since shortly after the announcement of her husband's prize, although she has never been accused of any crime. Reporters Without Borders on Friday released a video it said showed her smoking at her window – the first glimpse of her for almost two years. The footage could not be verified independently, but the silhouetted figure resembled her.

"The video of Liu Xia that we are releasing today is very short and lacks detail, but is very symbolic. Smoking a cigarette at her window is one of the few freedoms left to her. The difficulty of obtaining this footage is also indicative of the isolation imposed on her and the danger to which anyone trying to approach her home is exposed," the group said.

Chinese authorities insist Liu is not being held against her will. But a source close to the family told the BBC this week there were two female police officers living in her flat and numerous plainclothes police watching her block. The source said officials hoped pressure on Liu would force her husband to agree to go into exile – a choice he has always spurned.

The source said Liu Xia was "suffering mentally". She is allowed to see her husband every two or three months and otherwise is allowed out only once a month or so, to visit her mother and one of her close friends under escort.

Before her detention, the poet told the Guardian she was not particularly interested in politics and seldom read her husband's works, adding: "But when you live with such a person, even if you don't care about politics, politics will care about you."