Aust wants Chinese dissident's widow freed

Australia is urging China to lift travel restrictions on the wife of a deceased Nobel Prize-winning dissident and release her from home detentions.

Foreign Minister Julie Bishop says the death of Liu Xiaobo on Thursday was very sad.

The democracy advocate died of multiple organ failure during treatment for late-stage liver cancer.

Ms Bishop said Australia had raised his plight with Chinese officials many times since his jailing in 2009.

"The desire for greater freedom, the desire to have a say in who governs you are irresistible human desires and that's all that Liu Xiaobo was doing," she told ABC TV on Sunday.

"We have a ministerial level human rights dialogue with China so we have an opportunity to make our concerns known directly with the Chinese officials and I certainly raise our concerns on every ministerial meeting that I have with my Chinese counterpart."

His widow Liu Xia has been under effective house arrest since her husband won the Nobel Peace Prize in 2010, but had been allowed to visit him in prison about once a month.

"We call upon the Chinese government to lift any travel restrictions on his wife and to release her from house detention," Ms Bishop said.

A Chinese government official told reporters Liu Xia "is free" but would not reveal her whereabouts, Reuters reported on Friday.