China on Thursday hailed the late Henry Kissinger as an "old friend", paying tribute to a diplomat central to establishing ties between Beijing and Washington.

Kissinger, a former US secretary of state whose unapologetic promotion of raw American power helped shape the post-World War II world, died on Wednesday, his consulting firm said. The diplomat, who lived to 100, had a mixed legacy internationally, seen by many as an unindicted war criminal for his roles in conflicts in Southeast Asia and the overthrow of democratically-elected governments.

But in China, he is granted the sobriquet of "old friend of the Chinese people" for his part in establishing ties back in the 1970s.

"It is a tremendous loss for both our countries and the world," Chinese ambassador to the US Xie Feng said in a post on social media platform X.

"History will remember what the centenarian had contributed to China-US relations, and he will always remain alive in the hearts of the Chinese people as a most valued old friend," he added.

CCTV hailed his "historic contribution to the opening of the door to US-China relations".

Kissinger, it said, was "an important witness who experienced the establishment of diplomatic relations between China and the United States and the development of the relationship between the two countries".

In Japan, Prime Minister Fumio Kishida hailed Kissinger's "significant contributions" to peace and stability in Asia.

Kissinger "made significant contributions to the regional peace and stability, including the normalisation of diplomatic ties between the US and China," Kishida told reporters.

"I'd like to express my most sincere respect to the great achievements he made," Kishida added. "I also would like to offer my condolences." (AFP)