TOKYO (UPDATE) - The United States is committed to defending Taiwan if China attempts to seize the self-ruled island by force, President Joe Biden said Monday, in what seems as a shift from Washington's long-standing policy to keep its stance ambiguous.

Asked by a reporter if the United States is willing to get involved militarily in a Taiwan contingency, Biden told a press conference after meeting with Japanese Prime Minister Fumio Kishida in Tokyo, "Yes. That's the commitment we made."

Biden said the United States maintains its one-China policy under which it recognizes Beijing as the "sole legal government of China."

But the idea that Taiwan can be taken by force is "just not appropriate" and it will "be another action similar to what happened in Ukraine," he said, referring to Russia's invasion of its neighbor that began in late February.

The U.S. president's remarks reflected the growing concerns over China's assertiveness in the region, including over Taiwan, which Beijing regards as a renegade province awaiting reunification by force if necessary.

The U.S. government has maintained an ambiguous position regarding the use of military force in response to a Chinese attack on Taipei, a stance known as "strategic ambiguity."

The strategic ambiguity policy was adopted after Washington switched diplomatic recognition from Taipei to Beijing in 1979, with U.S.-Taiwan ties becoming unofficial.

The policy is intended not only to deter China from using force against Taiwan but also to dissuade Taiwan from seeking independence, as neither Beijing nor Taipei can feel certain the United States would intervene to defend the island should a conflict arise, according to experts.

It is not the first time that Biden has made remarks about coming to Taiwan's defense in the event of an attack. He gave a similar answer during a town hall event organized by CNN in October.

At that time, the White House said later there was no change in policy toward the island.

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