Writers demand release of Chinese Nobel laureate's widow

More than 50 international authors have requested the release of Liu Xia, the widow of a high-profile Chinese dissident, in an open letter sent to Chinese President Xi Jinping.

Liu Xia is the widow of Liu Xiaobo, a Chinese activist who was awarded the Nobel Peace Prize in 2010 for promoting civil liberties and human rights. He was the co-author of "Charter '08," a document calling for democracy and the end of China's one-party system.

He was imprisoned in 2009 for subversion of state power and died of cancer in July while still under state surveillance.

Liu Xia was last seen in public at his funeral, and friends suspect she remains under some form of detention. She has been under unofficial house arrest since 2010.

"We ask you to remove all remaining restrictions on Liu Xia, including over her freedom of movement, and to permit her to meet and speak freely with others including her family, friends, and members of the media," said the letter signed by 53 authors associated with the non-profit organization PEN America.

"Liu Xia has undergone great suffering for many years, simply for being the wife of a man that China has deemed to be a dissident," the letter said. "She has committed no crime, and she has not been charged with any crime."

Signatories included Chimamanda Adichie, Margaret Atwood, John Coetzee, Susan Orlean, Philip Roth, George Saunders and George Packer.

The letter comes ahead of US President Donald Trump's first official visit to China next week, during which he might broach the topic of human rights.