Artist urges David Cameron on human rights talks in China

Chinese artist, Ai Wei Wei, has called for David Cameron to raise the issue of China's human rights on his trade mission to China.

The prime minister has arrived in China as part of a UK government and trade mission to the country.

The artist, who says he was recently released from a two day house arrest in China, currently has an exhibition of one hundred million hand-painted porcelain seeds at the Tate Gallery in London.