Chinese artist Ai Weiwei said he has been barred from a court hearing Wednesday against a multi-million-dollar tax fine linked to a firm he founded, and accused authorities of seeking to "crush" him. Ai, an internationally acclaimed artist also renowned for his activism, disappeared into custody for 81 days last year as police rounded up dissidents amid online calls for Arab Spring-style protests in China. Upon his release, he was accused of tax evasion linked to Fake Cultural Development Ltd -- a company he founded, but which is legally registered in his wife's name. Lawyers for Fake have lodged an appeal against the charges, which Ai says are politically motivated and have no basis. He has accused the tax bureau of failing to follow correct procedures in the case. The 54-year-old said the bureau had never seen the full, original file brought against the company, which the police still hold, and Fake's lawyers had also not been allowed to review the evidence. "How can you accuse someone but not give them the right to ask where this allcame from?" he asked. "They are not professional and never intended to be professional, they just want to crush me." In November, the Beijing tax bureau issued a bill for 15 million yuan ($2.4 million) in alleged back taxes, giving the artist 15 days to pay it or hand over an 8.45-million-yuan guarantee. Ai was able to pay the guarantee -- needed by law to challenge the charge -- thanks to a wave of donations from supporters. In April, lawyers for Fake filed a lawsuit against the tax bureau, which is being heard later Wednesday. "They (police) have made clear their decision -- they said 'if you try to get to court, you will never get there'," Ai, who had planned to attend proceedings, told AFP. He said his wife Lu Qing, who is Fake's legal representative, will be attending. Ai was released on bail on June 22, 2011, and barred from leaving Beijing for one year. This restriction expires on Friday, but it remains unclear whether he will be allowed to travel out of the capital. The artist -- named the world's most powerful art figure by influential British magazine Art Review last year -- is renowned for his political activism, which has repeatedly angered the ruling Communist Party. He riled authorities with his investigation into the collapse of schools in the 2008 Sichuan earthquake and into a 2010 fire at a Shanghai high-rise that killed dozens.