Chinese President Xi Jinping sent a message of condolence on Wednesday to the new Kuwaiti emir Sheikh Nawaf Al-Ahmad Al-Jaber Al-Sabah over the death of Sheikh Sabah Al-Ahmad Al-Jaber Al-Sabah, who had ruled the Middle Eastern country since 2006.

Xi said that he, on behalf of the Chinese government and the Chinese people, as well as in his own name, extends deep condolences over the passing of the late emir and expresses sincere sympathies to his family and the Kuwaiti people.

Sheikh Sabah Al-Ahmad Al-Jaber Al-Sabah, 91, died on Tuesday in the United States, where he was receiving medical treatment.

Sheikh Sabah Al-Ahmad Al-Jaber Al-Sabah was an outstanding leader of Kuwait and had made significant contributions to promoting regional peace and development, Xi said.

The late emir highly valued developing Kuwait's relations with China and made an outstanding contribution to pushing forward the friendly bilateral cooperation in all areas, he said, adding that he was deeply saddened that the Chinese people have lost a sincere old friend.

Xi said that he attaches great importance to the traditional friendship between the two countries and believes that the bilateral strategic partnership will continue to be consolidated and developed with joint efforts from both sides.

Emir Sheikh Nawaf Al-Ahmad Al-Jaber Al-Sabah, 83, is a half brother of his predecessor.

On Wednesday, Chinese Premier Li Keqiang sent a message of condolence to Kuwaiti Prime Minister Sheikh Sabah Al-Khalid Al-Sabah.

The Amiri Diwan, which serves as the royal palace of the Kuwaiti emir, said in a statement: "With great sadness and sorrow, the Amiri Diwan mourns the passing of His Highness, the late Emir of Kuwait Sheikh Sabah Al-Ahmad Al-Jaber Al-Sabah."

A government statement said: "With his passing, Kuwait, the Arab and Islamic regions and humanity as a whole have lost a distinguished icon."

40-day mourning

The government announced 40 days of mourning for the emir's death and closed government and official institutions for three days from Tuesday.

On July 18, the ruler was admitted to hospital for a medical checkup and had a "successful" surgery a day later, the Kuwait News Agency quoted Minister of Amiri Diwan Sheikh Ali Jarrah Al-Sabah as saying. On July 23, the emir left for the US to complete medical treatment.

Sheikh Sabah Al-Ahmad Al-Jaber Al-Sabah in 2014 was honored by the United Nations with the title of Humanitarian Leader for his efforts in humanitarian work.

Sheikh Nawaf Al-Ahmad Al-Jaber Al-Sabah had been the crown prince since February 2006.

Xinhua contributed to this story.