The US has reportedly demanded commitments from its allies in the event of a war over Taiwan

The Pentagon is pressuring key US allies in the Indo-Pacific - Japan and Australia - to clarify their positions in the event of a war with China over Taiwan, the Financial Times reported on Sunday.

Beijing views Taiwan as part of its territory according to the One-China principle, and insists on eventual reunification. While the US officially acknowledges Chinese sovereignty over the self-governing island, it continues to supply Taipei with weapons.

US Under Secretary of Defense Elbridge Colby has for months been pushing Japanese and Australian military officials to prepare for a potential conflict, the outlet wrote, citing anonymous sources.

"Concrete operational planning and exercises that have direct application to a Taiwan contingency are moving forward with Japan and Australia," the FT cited one of its sources as saying. "But this request caught Tokyo and Canberra by surprise because the US itself does not give a blank check guarantee to Taiwan."

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According to Colby, the Defense Department is focused on US President Donald Trump's agenda of "restoring deterrence and achieving peace through strength." However, "some among [Washington's] allies might not welcome frank conversations," Colby wrote on X on Saturday.

Australian Defense Industry Minister Pat Conroy refused to "engage in hypotheticals" when asked to comment on reports of US pressure over China. Canberra has "the sole power to commit Australia to war or to allow our territory to be used for a conflict," he told ABC on Sunday.

Tensions in the Taiwan Strait have risen since Taiwan elected pro-independence President Lai Ching-te last year. Trump has reengaged China in a trade war since taking office, although the escalation has somewhat subsided after Washington and Beijing settled a rare-earths deal last month.