China cautions citizens against traveling to Japan

While the advisory does not prohibit China's citizens from going to Japan, the warning is the most serious rebuke of the Japanese prime minister's comments so far, according to CNN.

Hong Kong's Security Bureau on Saturday issued a similar notice to its residents.

Seven Chinese airlines also told passengers who are scheduled to fly to Japan that they will refund ticket prices or allow ticketholders to change their flight routes through the end of the year.

The travel warnings came after Takaichi last week told lawmakers Japan could use its military to intervene in any conflict that might occur in the Taiwan Strait that separates Taiwan from mainland China.

She said any military action against Taiwan by China would create a self-defense situation that could trigger a military response from Japan.

Chinese officials have demanded the prime minister retract her comments, including one official who referred to her as an "evil witch" and another who mentioned cutting off a "dirty neck" that stuck itself into Chinese matters, NBC News reported.

Takaichi so far has refused to retract her comments, though, according to China Daily.

China has laid claim to Taiwan and has hinted at using military force, if necessary, to assert its territorial claim to the self-ruling island nation that became the refuge of Chinese nationalists after communist forces took control of the mainland in 1949.

The prime minister's comments also drew a rebuke from former Prime Minister Shigeru Ishiba.

Ishiba, during a radio interview on Thursday, said Takaichi's comments were "very close to claiming that a Taiwan contingency is a Japan contingency."

Other national leaders had avoided saying how the Japanese government might respond to matters in Taiwan under certain situations, he added.