Ai Weiwei, the Chinese artist-activist who was detained by the Chinese government in 2011, is coming back to the US for the first time since his travel ban was lifted. His visit is timed to coincide with the show Andy Warhol-Ai Weiwei, which is due to travel from Australia to the Andy Warhol Museum in Pittsburgh (4 June-28 August). Ai was given back his Chinese passport in July 2015 and has travelled widely since. He is likely to come to New York, where he lived in the 1980s. Ai never met Warhol, but in 1987, the year the Pop artist died, he took a photograph of himself in front of Warhol’s self-portrait, entitling it At the Museum of Modern Art. At the fair, Ai’s porcelain Cube (2009) is on sale at Lisson Gallery (B62, €220,000).