Beijing, China (CNN) -- Dissident artist Ai Weiwei has been released on bail -- apparently with conditions -- after he spent nearly three months in prison on charges of tax evasion, the state-run Xinhua news agency reported Wednesday.
"I'm fine," Ai told a group of reporters and sympathizers who gathered in front of his home and studio in Beijing hours after his release. Looking haggard and thinner, the artist managed a smile but declined to answer questions. "I'm sorry I can not talk," he said. "I am on probation, please understand."
Observers in Beijing say it may not be coincidental that Ai's release on Wednesday takes place on the eve of Premier Wen Jiabao's upcoming visit to Hungary, the UK and Germany, where Ai enjoys wide support among artists and politicians.
Renowned as a provocative conceptual artist, Ai is equally well known as an outspoken commentator and a harsh, uncompromising critic of Chinese government policies.
Most famous for designing the Bird's Nest stadium for the 2008 Beijing Olympics, Ai later called for a boycott of the games because he said China was using them as propaganda.
Ai also has accused the Chinese government of trying to silence dissidents.
He was seized April 3 while planning to board a plane to Hong Kong and later accused of economic crimes, a move that prompted international condemnation and added to criticism over China's controversial record on human rights.
He was not formally charged or tried.
Ai's Beijing studio was raided, and his wife and eight assistants were taken into custody for questioning.
Beijing police accused him of evading a "huge amount" of taxes, Xinhua reported in May, more than a month after he was detained.
In addition, investigators accused Ai's company of intentionally destroying accounting documents.
Jerome Cohen, adjunct senior fellow for Asia studies at the Council on Foreign Relations, said that under the bail conditions, Ai has "lost his freedom of speech" for at least a year."
"He will not soon again be on Twitter, Facebook, television, take part in fora, etc. He's got to keep quiet and behave according to the criteria of the Chinese police for the foreseeable future. He's not the only one. This has happened many times before," said Cohen, also a professor at NYU School of Law.
No one heard from him for 43 days after his detention began, said his mother, Gao Ying.
Ai Weiwei's wife, Lu Qing, was allowed to visit him May 15, Ai's mother said two days after the visit.
Xinhua quoted police May 20 as saying Ai is "living under surveillance" and officials have guaranteed his legal rights, including the right to meet family.
Beijing police told state media that Ai had been released on bail because of his good attitude in confessing his alleged crimes and also said he was suffering from a chronic disease. It is not clear to what disease police were referring.
Ai has also said that he is willing to pay the taxes he allegedly evaded, police told Xinhua.
Relatives and human rights groups said they believe Chinese authorities targeted him because of his irreverent commentary on modern Chinese society. The Chinese government has denied his activism had anything to do with its actions.
"He is not alone in this position and in fact shares it with many human rights lawyers, writers, activists and young people online," filmmaker Alison Klayman recently told CNN.
"A lot of the censorship that happens in China is self-censorship, and I think the fact that Weiwei doesn't engage in self-censorship is a big reason why people gravitate to him," said Klayman, whose feature film "Ai Weiwei: Never Sorry" is set to be released this fall.
His prolonged detention sparked international outcry, especially among artists and museum officials in the United States and Europe. He became a rallying point among human rights activists overseas who condemned China's crackdown on political dissidents, lawyers, artists and religious groups.
Some commentators said they believe the arrests may have been launched in response to fears over the unrest that has swept the Middle East.
More than 130 activists have been detained in China since February following the government crackdown, according to Amnesty International.
"It is vital that the international outcry over Ai Weiwei be extended to those activists still languishing in secret detention or charged with inciting subversion," said Catherine Baber, deputy Asia-Pacific director for the organization.
"His release can be seen as a tokenistic move by the government to deflect mounting criticism," she said, noting that four Ai associates -- Wen Tao, Hu Mingfen, Liu Zhenggang and Zhang Jinsong -- are still being secretly detained.
Ai was conspicuously absent during the May opening of his latest exhibition, "Circle of Animals/Zodiac Heads," in London.
CNN's Jaime FlorCruz and Haolan Hong contributed to this report.