Chinese President Xi Jinping (R) holds talks with British Prime Minister David Cameron at 10 Downing Street in London, Britain, Oct. 21, 2015. (Xinhua/Ju Peng)

Chinese President Xi Jinping (R) holds talks with British Prime Minister David Cameron at 10 Downing Street in London, Britain, Oct. 21, 2015. (Xinhua/Ju Peng)

Chinese President Xi Jinping (R) holds talks with British Prime Minister David Cameron at 10 Downing Street in London, Britain, Oct. 21, 2015. (Xinhua/Ju Peng)

Chinese President Xi Jinping (3rd R) holds talks with British Prime Minister David Cameron at 10 Downing Street in London, Britain, Oct. 21, 2015. (Xinhua/Ju Peng)

Chinese President Xi Jinping (L, back) and British Prime Minister David Cameron meet media after their talks at 10 Downing Street in London, Britain, Oct. 21, 2015. (Xinhua/Rao Aimin)