Ai Weiwei
Ai Weiwei has been allowed to stay in the UK on a six month visa after an order by Home Secretary Theresa May Reuters

Home Secretary Theresa May has granted Chinese artist Ai Weiwei a six-month visa to stay in the UK for his exhibition following a U-turn decision.

Ai Weiwei, who is famous for designing Beijing's Olympic Stadium, was initially refused to stay longer than allowed on his three-week visa after failing to declare his "criminal conviction". But he was never charged or convicted of any crime when he was detained in China for 81 days in 2011.

The Home Office has since sent him a letter of apology for "any inconvenience caused" and claims the home secretary was not consulted over the initial decision to refuse his one-month visa.

A Home Office spokesman said: "She has reviewed the case and has now instructed Home Office officials to issue a full six-month visa. We have written to Mr Ai apologising for the inconvenience caused." He will be exhibiting his work at the Royal Academy of Arts in London in September.