Chinese President Xi Jinping (L, front) is welcomed by Deputy Crown Prince Mohammed bin Salman and other officials upon his arrival in Riyadh, Saudi Arabia, Jan. 19, 2016. Xi arrived here on Tuesday for a state visit to Saudi Arabia, the first stop of his three-nation tour of the Middle East. (Xinhua/Ju Peng)

Chinese President Xi Jinping holds talks with Saudi King Salman bin Abdulaziz Al Saud in Riyadh, Saudi Arabia, Jan. 19, 2016. Xi arrived here on Tuesday for a state visit to Saudi Arabia, the first stop of his three-nation tour of the Middle East. (Xinhua/Ju Peng)

Chinese President Xi Jinping (C) attends a welcoming ceremony held by Saudi King Salman bin Abdulaziz Al Saud (L, front) for him before their talks in Riyadh, Saudi Arabia, Jan. 19, 2016. Xi arrived here on Tuesday for a state visit to Saudi Arabia, the first stop of his three-nation tour of the Middle East. (Xinhua/Ju Peng)

Chinese President Xi Jinping (L) meets with Secretary General of the Organization of the Islamic Cooperation (OIC) Iyad Ameen Madani in Riyadh, Saudi Arabia, Jan. 19, 2016. Xi arrived here on Tuesday for a state visit to Saudi Arabia, the first stop of his three-nation tour of the Middle East. (Xinhua/Wang Ye)

Chinese President Xi Jinping (L) meets with Saudi Deputy Crown Prince Mohammed bin Salman in Riyadh, Saudi Arabia, Jan. 19, 2016. Xi arrived here on Tuesday for a state visit to Saudi Arabia, the first stop of his three-nation tour of the Middle East. (Xinhua/Wang Ye)

Chinese President Xi Jinping (L) meets with Gulf Cooperation Council (GCC) Secretary-General Abdul Latif Bin Rashid Al Zayani in Riyadh, Saudi Arabia, Jan. 19, 2016. Xi arrived here on Tuesday for a state visit to Saudi Arabia, the first stop of his three-nation tour of the Middle East. (Xinhua/Wang Ye)

Chinese President Xi Jinping (L) and Saudi King Salman bin Abdulaziz Al Saud inaugurate the operation of the Yasref oil refinery, a joint venture between Saudi Aramco and China's Sinopec in Riyadh, Saudi Arabia, Jan. 20, 2016. (Xinhua/Ma Zhancheng)

Chinese President Xi Jinping (L front) and Saudi King Salman bin Abdulaziz Al Saud (R front) inaugurate the operation of the Yasref oil refinery, a joint venture between Saudi Aramco and China's Sinopec in Riyadh, Saudi Arabia, Jan. 20, 2016. (Xinhua/Ma Zhancheng)

Chinese President Xi Jinping (L front), accompanied by Saudi King Salman bin Abdulaziz Al Saud(R front), visits the Murabba' Palace, named after its square form of 400 by 400 meters in Riyadh, Saudi Arabia, Jan. 20, 2016. (Xinhua/Ju Peng)

Chinese President Xi Jinping (L) and Saudi King Salman bin Abdulaziz Al Saud(R front) taste traditional Arab coffee during his visit to the Murabba' Palace, named after its square form of 400 by 400 meters in Riyadh, Saudi Arabia, Jan. 20, 2016. (Xinhua/Ju Peng) 10