US President Joe Biden has reiterated the policy of "strategic ambiguity" in dealings with China and Taiwan.

"No.

The policy hasn't changed at all," Biden said in Tokyo on Tuesday when a reporter asked whether Washington's previous line no longer applied.

Biden on Monday brought up military support for Taiwan in the event of an attack by China.

When asked by a journalist whether the United States could "participate militarily to defend Taiwan," unlike in Russia's war of aggression against Ukraine, Biden said "yes."

He then added, "That's the commitment we made."

The statement immediately caused a stir and sharp reactions from China, even though Biden had already made similar statements last October.

China accused Biden of "playing with fire".

The US has long pursued a line of "strategic ambiguity" on this issue.

In doing so, they assure Taiwan of support in building up its defense capabilities, but do not expressly promise to come to the island's aid in the event of war.

Beijing sees Taiwan as a breakaway province that is to be reunited with the mainland, if necessary using military force.

The United States has recognized the leadership in Beijing as China's sole government since 1979.

However, Biden emphasized on Monday that this does not mean that China can take Taiwan by force.

"That is not appropriate."

After Biden's comments, US Secretary of Defense Lloyd Austin emphasized that the government had not changed course in Taiwan policy.

"Our politics haven't changed," Austin told reporters.

"As the president said, our one-China policy hasn't changed." At the same time, Biden reaffirmed the statutory pledge to help Taiwan obtain the means to "defend itself."

Shortly after Biden's statement, a White House official asserted that the President's words were consistent with America's existing policy towards Taiwan.

"Our policy has not changed."