A pro-democracy activist mourns the death of Nobel Laureate Liu Xiaobo outside China's Liaison Office in Hong Kong on July 13. (Bobby Yip/Reuters)

Chinese writer Liu Xiaobo died Thursday at age 61. Liu was one of his country's best-known dissidents and became the only Chinese national to win the Nobel Peace Prize in 2010. But his activism against one-party rule came at a huge personal cost: When he won the Nobel, he was in the middle of a lengthy prison sentence for his promotion of democracy.

Liu was granted medical parole in late June as the Chinese government revealed that he had late-stage liver cancer, but he died under the close guard of authorities. He is the first Nobel Peace Prize winner to die in state custody since 1938, when German pacifist Carl von Ossietzky died after years in Nazi Germany's concentration camps.

The circumstances of Liu's death drew commiseration from around the world. However, the response from the leader of the United States was comparatively muted. The White House released a short statement Thursday that said President Trump was “deeply saddened” by the news of Liu's death, noting that he was a “poet, scholar and courageous advocate” who had “dedicated his life to the pursuit of democracy and liberty.”

Many activists said that the White House statement was undercut by comments Trump himself made earlier in the day. The president had been holding a news conference in Paris with French President Emmanuel Macron when a reporter  asked him what he thought personally of Xi Jinping, the Chinese president.

“Well, he’s a friend of mine,” Trump responded. “I have great respect for him. We’ve gotten to know each other very well. A great leader. He’s a very talented man. I think he’s a very good man. He loves China, I can tell you. He loves China. He wants to do what’s right for China.”

Xi has been leader of China since 2013 and oversaw the country during four years of Liu's detention. Activists say that under Xi, the Chinese state has grown more repressive and activists more threatened.

“The future for human rights in China gets ever bleaker under the leadership of President Xi Jinping,” Sophie Richardson, China director at Human Rights Watch, said this year. “The authorities have targeted rights-promoting groups and boldly strengthened efforts to control them.”

Though Trump has frequently criticized China for its trade policies and economic relationship with North Korea, he has shied away from commenting on human rights abuses in the country. The U.S. president has met with Xi a number of times and spoken warmly of his personal relationship with him on a number of occasions.

Trump's praise for Xi is disappointing to many Chinese activists.

“Trump has shown so little interest in human rights since he came to power, and sometimes he even shows contempt for human rights issues,” Hu Jia, a prominent Chinese dissident and Liu family friend, told the Guardian newspaper.

Trump isn't the first U.S. president to tread lightly on the subject of human rights. Though President Barack Obama raised the issue of Liu's detention shortly after the activist won the Nobel Peace Prize, he too shied away from commenting on it at other times, and threatened to veto a Senate bill that would have renamed the street in front of the Chinese Embassy “Liu Xiaobo Plaza.”

Though the White House issued only a short statement on Liu's death, other branches of the U.S. government issued more detailed responses to the news.

In a statement, Secretary of State Rex Tillerson called it a “tragic passing” and called on the Chinese government to release Liu's wife, Liu Xia, from house arrest. “In his fight for freedom, equality and constitutional rule in China, Liu Xiaobo embodied the human spirit that the Nobel Prize rewards. In his death, he has only reaffirmed the Nobel Committee’s selection‎,” the statement read.

Incoming Ambassador to China Terry Branstad also offered a longer statement that echoed Tillerson's call to release Liu Xia.

“China has lost a deeply principled role model who deserved our respect and adulation, not the prison sentences to which he was subjected,” Branstad wrote.

But the strongest statements came from outside the administration. Sen. John McCain (R-Ariz.) called the Chinese government's delay in getting treatment to the imprisoned activist “the last barbaric violation of Dr. Liu’s human rights.” Former president George W. Bush also issued a statement, saying Liu was a political prisoner of conscience who had “dared to dream of a China that respected human rights.”

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Don’t gawk at pictures of jailed Nobel laureate Liu Xiaobo on his deathbed. Read his words.