Dissident Chinese artist Ai Weiwei has gotten back his passport four years after it was confiscated by Beijing authorities and plans to attend a London exhibition in September.

The artist and government critic posted an Instagram photo on Wednesday of himself holding a Chinese passport with the caption, "Today, I got my passport."

Ai Weiwei designs on the Serpentine, from afar

Ai's representative confirmed the passport had been returned, but did not immediately respond to further questions.

Ai was on his way to Hong Kong from Beijing, when he was detained by authorities for about three months in 2011, but not charged. His design firm later was slapped with a $2.4m tax bill, which he fought unsuccessfully in Chinese courts.

Chinese authorities often deny passports to dissidents who might embarrass the ruling Communist Party overseas.

Ai's work has gotten much attention worldwide, making him one of best-known Chinese dissidents.

Britain's Royal Academy of Arts said Ai would travel to London for a major exhibition of his work in September.

"This is wonderful news for Ai Weiwei, his family and for artists worldwide," said Royal Academy director Tim Marlow. "We are delighted to announce that he will be joining us as we finalise the installation of his exhibition."

Ai's work is very popular in Britain. In 2010 he filled a vast hall at the Tate Modern gallery with 100 million ceramic sunflower seeds.

Visitors were initially invited to walk or lie on them, but after a few days the ceramic dust was judged a health hazard and the exhibit was cordoned off. It still attracted large crowds.

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A photo posted by Ai Weiwei (@aiww) onJul 21, 2015 at 11:51pm PDT

 

New York Times report also said that Ai plans to travel to Germany soon. 

Before his detention, Ai had spoken out about a number of national scandals, including the deaths of students in shoddily built schools that collapsed during a massive earthquake in 2008.

The government has blacklisted him from any mention in state media, and he is not allowed to post anything on China's social media.

Source: Al Jazeera and agencies