China unexpectedly recalled its ambassador to India shortly before a state visit to the country this month by President Xi Jinping. The move came as news emerged about the mysterious disappearance of another Chinese diplomat in Iceland who was alleged to have spied for Japan.

Xinhua, the Chinese news agency, announced the day before Mr Xi’s arrival in India that Wei Wei had been replaced as ambassador in New Delhi by Le Yucheng, who had been posted in Kazakhstan.

Several senior diplomats from other countries said they were baffled by the move but there was no agreement on the possible causes. They said Mr Wei might have been shunted out to make way for one of Mr Xi’s loyalists, or fallen foul of an anti-corruption campaign that has brought down tens of thousands of Chinese officials since it began early last year.