BEIJING — Ai Weiwei, the rebel artist and acid critic of the Chinese Communist Party who was detained by the government last year, said Tuesday that authorities were still holding his passport, which means he cannot travel to the United States for long-planned artistic events there next month or start a job as a visiting professor in Germany.
Ai said in a telephone interview that he would be unable to attend the opening on Oct. 7 of the first survey of his work in North America. The exhibition is being prepared at the Hirshhorn Museum in Washington, one of the Smithsonian museums supported by the US government. Ai said that he also expected to be forced to cancel an appearance at a literary festival in New York that promotes freedom of speech and that he would be unable to give talks at Harvard, Princeton, and New York universities.
‘‘They’re still holding my passport,’’ Ai said. ‘‘They said they want to give it to me but have no clear time schedule for that.’’
Ai was detained for 81 days last year and put on probation for one year after his release. That probation ended June 21. Ai said at the time that police officers in Beijing had told him that he could not leave China but that he would soon have his passport returned.
‘‘I think it’s that the person who’s responsible for my case didn’t get a clear order from above,’’ he said. ‘‘And maybe the people from above are busy with much more important issues.’’
With a once-a-decade leadership transition expected to take place this fall, Chinese officials are watchful for any potential trouble. Written requests for comment, sent to both the headquarters of the Beijing police and the Foreign Ministry, went unanswered Tuesday.
It was unclear whether American officials are negotiating with the Chinese government to allow Ai to travel to the United States. An embassy spokesperson did not return a request for comment. The Smithsonian Institution has written the Chinese culture minister reaffirming the invitation for Ai from the Hirshhorn.
While in detention, Ai was interrogated on, among other things, the value of his artwork, and tax officials later said he owed $2.4 million in back taxes and penalties. Ai sued the tax authorities in a Beijing court, but the court ruled against him. Ai appealed the ruling at a higher court; he said court officials were expected to announce a decision Thursday.