BeijingThe widow of Nobel Laureate and democracy activist Liu Xiabo, who died of cancer in detention last year, was allowed to leave China on Tuesday after several years of de-facto house arrest without being formally charged for any crime.Liu Xia, 57, boarded a flight to Berlin after a diplomatic campaign by the German government to free her.Chinese Premier Li Keqiang is currently on a visit to Germany.Her husband Liu won the Nobel Peace Prize in 2010 but wasn’t allowed by the Chinese government to collect the award. He was among the key leaders of the pro-democracy Tiananmen protests of 1989. He was jailed several times and marked as a dissident by the Chinese government.He died of liver cancer last year in a government hospital and his ashes were scattered at sea.Liu Xia was also put under house arrest with intermittent access to family and friends. The poet and artist was never charged with a crime.When her longtime friend, Liao Yiwu, a Chinese author based in Berlin, spoke to her over phone in May, Liu Xia said she was ready to die in protest at her continuous house arrest.“Now, I’ve got nothing to be afraid of. If I can’t leave, I’ll die in my home. Xiaobo is gone, and there’s nothing in the world for me now. It’s easier to die than live. Using death to defy could not be any simpler for me,” Liu Xia told Liao, reported the website China Change, which publishes write-ups by Chinese dissidents.Berlin had responded by saying Liu Xia was welcome to come to Germany at anytime.“According to the information available to us, Liu Xia has not been accused of any crime. She should be allowed to travel, also for humanitarian considerations. Should she choose to come to Germany, Liu Xia would be welcome here at any time,” the German foreign ministry had said in emailed comments to the Associated Press.