Henry Kissinger, a veteran US diplomat, said on Monday that the US and China need to avoid confrontation in order to maintain global peace.
President Joe Biden said the U.S. would intervene if China invaded the island.
Biden's remarks appeared to mark a break in Washington's longstanding tradition of strategic ambiguity over Taiwan. The White House said the comments do not reflect a change in policy.
Speaking at the World Economic Forum, Kissinger said that the United States should not use subterfuge or a gradual process to find a solution to the China issue.
Taiwan cannot be the core of the negotiations because it is between China and the United States.
Biden told reporters at a news conference that the US would defend Taiwan if Beijing invaded.
The Foreign Ministry of China expressed strong discontent and opposition to the comments.
The U.S. acknowledges China's position that there is only one Chinese government.
Washington supplies military equipment to the island in accordance with the 1979 Taiwan Relations Act. This act does not require the U.S. to intervene in the event of a Chinese invasion of Taiwan, but it does require the island to have the resources to defend itself and to deter Beijing from unifying the island.
Taiwan is a democratic island that China claims is part of its territory.
For the core of the negotiations, it is important that the United States and China discuss principles that affect the relationship between the two countries.
It is important for the peace of the world for the United States and China to have a good relationship.
Kissinger was secretary of state and national security under Republican Presidents Richard Nixon and Gerald Ford.
During his time in office, Kissinger influenced some of the most important turns in U.S. foreign policy. The U.S. had relations with China.
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