Former U.S. Secretary of State Henry Kissinger, who played a pivotal role in opening ties with China in the 1970s and continued to shape Washington's foreign policy, died Wednesday at his home in Connecticut, his consulting firm said. He was 100.

Kissinger was arguably the most powerful secretary of state in the 20th century whose accomplishments included helping the United States exit from the Vietnam War through the Paris Peace Accords and thaw relations with the Soviet Union by pursuing a policy of detente.

Even after retiring from government service in 1977, Kissinger advised numerous U.S. and foreign leaders, and wrote more than 20 books on national security issues.

He was active in global affairs until recently, such as holding a meeting with Chinese President Xi Jinping in July in Beijing. Xi expressed his "deep condolences" over Kissinger's death in a message sent to U.S. President Joe Biden, the Chinese Foreign Ministry said.

Former U.S. Secretary of State Henry Kissinger is pictured at the White House in October 2017, in Washington. (AP/Kyodo)

Foreign Ministry spokesman Wang Wenbin said at a press conference Kissinger was "a dear old friend of the Chinese people" as well as a trailblazer and contributor to the development of Sino-U.S. relations as he visited the Asian country more than 100 times.

Wang said China and the United States "need to carry forward his strategic vision, political courage and diplomatic wisdom" and "work for the healthy, stable and sustainable development" of bilateral relations.

Japanese Prime Minister Fumio Kishida hailed Kissinger's role in ensuring regional peace and stability through the normalization of U.S.-China relations. "I offer my heartfelt respect to his great achievements and extend sympathy" over his death, the premier told reporters.

Kissinger will be interred at a private family service and a memorial service will be held in New York City at a later date, according to a statement released by Kissinger Associates Inc.

Kissinger, a Jew who fled to the United States with his family from Nazi Germany in 1938, was the top U.S. diplomat under Republican presidents Richard Nixon and Gerald Ford.

He became a naturalized U.S. citizen in 1943 and earned all of his degrees at Harvard University following army service during World War II. After teaching international relations for nearly two decades at the university, he started serving as Nixon's national security adviser in 1969.

The scholar-turned-diplomat, who cherished realism in foreign policy rather than promoting lofty ideals, secretly traveled to Beijing in 1971 and set the stage for Nixon's surprise visit to China the following year.

The outreach to China made by Kissinger, the architect of the so-called triangular diplomacy, was aimed at driving a wedge in Sino-Soviet relations and extracting concessions from Moscow, the greatest enemy of Washington at the time, in negotiations on arms control.

Russian President Vladimir Putin offered condolences in a message to Kissinger's wife Nancy, calling the U.S. diplomat "a wise and far-sighted statesman who enjoyed well-deserved respect around the world for decades."

"Henry Kissinger's name is inextricably linked with America's pragmatic foreign policy, which played a pivotal role in defusing international tensions at the time and achieving crucial Soviet-American agreements that contributed to strengthening global security," he said, apparently referring to a deal on strategic arms limitations that was reached in 1972.

While winning a reputation as a skilled strategist, who maximized U.S. national interests and is respected in China for orchestrating the normalization of ties between the two countries in 1979, Kissinger was also a controversial figure.

He not only faced intense criticism for the bombing of Cambodia during the Vietnam War, but was seen as disregarding democratic values and human rights for backing anti-communist dictatorships.

Critics called Kissinger a war criminal. In 1973, along with North Vietnam's chief negotiator Le Duc Tho, he was awarded the Nobel Peace Prize for his efforts toward a cease-fire in Vietnam. The award stirred debate and is still regarded as one of the most controversial events in the peace prize's history.

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