WASHINGTON – US military forces will defend Taiwan if there is “an unprecedented attack”, President Joe Biden said on Sunday, underscoring America’s commitment to the island as Chinese incursions mount near its shores.

Mr Biden, speaking in a 60 Minutes interview aired on CBS, distanced himself from the question of whether Taiwan is or should be independent, but followed up with a pledge when asked by interviewer Scott Pelley if US forces would “defend the island”.

“Yes, if in fact there was an unprecedented attack,” he replied, according to a transcript provided by the broadcaster.

Asked to clarify if he meant that unlike in Ukraine, US forces – American men and women – would defend Taiwan in the event of a Chinese invasion, Mr Biden replied: “Yes.”

Still, he reiterated earlier in the interview that the United States’ “One China” policy has not changed.

“We agree with what we signed on to a long time ago, and that there is (a) One-China policy,” said Mr Biden, adding that Taiwan makes its “own judgments” about its independence.

“We are not moving; we are not encouraging their being independent,” he said. “That is their decision.”

Mr Biden has made similar statements before, spurring outrage in Beijing by adding new chapters to Washington’s longstanding policy of “strategic ambiguity” when it comes to Taiwan.

In May, Mr Biden said “yes” when asked if the US was prepared to become “involved militarily” if it had to.

“That is the commitment we made,” he said then, before White House officials walked back his comments.

A White House official said on Sunday that Mr Biden made the same points before and stressed that US policy has not changed. The official was responding to the 60 Minutes interview on condition of anonymity.

Washington cut formal diplomatic relations with Taiwan in 1979, switching recognition to Beijing as the sole representative of China, with the mainland becoming a major trading partner.

But at the same time, the US maintains a decisive, if at times delicate, role in supporting Taiwan.

Under a law passed by Congress, the US is required to sell Taiwan military supplies to ensure its self-defence against Beijing’s vastly larger armed forces.

But it has maintained what is officially called “strategic ambiguity” on whether it would actually intervene militarily. The policy is designed both to ward off a Chinese invasion and discourage Taiwan from ever provoking Beijing by formally declaring independence.

Since Mr Biden made his initial comments in May, tensions with China have flared after US House of Representatives Speaker Nancy Pelosi visited Taiwan.