China was already wary about Japan's new prime minister, renowned Beijing hawk Sanae Takaichi, before she weighed in on one of its most sensitive issues: Taiwan.

The saga began in late October when Ms Takaichi was questioned in parliament over how Japan would respond if China conducted a military blockade of Taiwan.

"I believe any action involving the use of force, such as China deploying naval ships, can only be described as a survival-threatening situation," she replied.

The phrase "survival-threatening situation" is a benchmark necessary for Japanese military involvement.

How one comment sparked threats against Japan's PM

Sanae Takaichi has been in the top job for less than a month, but her comments detailing what Japan could do if China invaded Taiwan has sparked a diplomatic war.

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