Beijing (AFP) - 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 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 and helping bring the country out of its Mao-era isolation.

And as US-China ties have plummeted in recent years, the elder statesman -- who visited the country more than 100 times -- became seen by many as emblematic of a more genteel, friendly time in Washington-Beijing relations.

"During his life, Dr. Kissinger attached great importance to China-US relations and believed that they were vital to the peace and prosperity of the two countries and the world," foreign ministry spokesperson Wang Wenbin said, describing him as an "old and good friend of the Chinese people".

Kissinger last visited China as recently as July, when he held talks with President Xi Jinping.

In a lengthy obituary on Thursday, Beijing's state broadcaster CCTV hailed his "historic contribution to the opening of the door to US-China relations".

"Kissinger had a deep bond with China," it said, noting his "many meetings with Chinese leaders".

As national security advisor to the then-US-president Richard Nixon, Kissinger secretly flew to Beijing in 1971 on a mission to establish relations with communist China.

The trip set the stage for a landmark visit by Nixon, who sought both to shake up the Cold War and enlist help in ending the Vietnam War.

Washington's overtures to an isolated Beijing contributed to China's rise to become a manufacturing powerhouse and the world's second-largest economy.

'Best and oldest friend'

Since leaving office, Nobel Peace Prize Laureate Kissinger grew wealthy advising businesses on China -- and had warned against a hawkish turn in US policy.

Chinese officials have struggled in recent years to hide their nostalgia for the days of rapprochement under Kissinger.

During a meeting with the late secretary of state in Beijing this year, top diplomat Wang Yi said that "US policy toward China needs Kissinger-style diplomatic wisdom".

And Beijing's foreign ministry on Thursday said the United States and China should "inherit and carry forward Dr. Kissinger's strategic vision, political courage, and diplomatic wisdom".

On the streets of Beijing, passersby said they were saddened by Kissinger's death.

"He was indeed the best and oldest friend of China," a tearful 67-year-old, who only identified himself by his surname of Li, told AFP.

"He gave everything to promote Sino-US relations," Zhang Wende, also in his late sixties, said.

"I am definitely very saddened, truly."

Another Beijing resident who only gave her surname, 35-year-old Dou, told AFP Kissinger's passing was a "loss for Sino-US relations" and that the former US diplomat had overseen a "honeymoon period" between the two countries.

"If he were still alive, I believe he would continue to make efforts for the relationship between China and the United States," she said.

Online, the late diplomat's death was among the top trending topics on both social media platform Weibo and the Google-like Baidu.

One user commented that the death represented a "watershed moment" at a time of China's ascension as a world power.

"From now on, it's the beginning of our rise and for the US to go down."