Japan urged China on Saturday to take “appropriate measures” after Beijing warned Chinese citizens against visiting Japan, Kyodo news agency reported, in an ongoing dispute over Taiwan.

Chief Cabinet Secretary Minoru Kihara said Japan had "conveyed the message to China and strongly asked it to take appropriate actions," the report said. It did not quote him as elaborating on the measures.

China on Friday cautioned its citizens against visiting Japan in the spat sparked by comments from Japanese Prime Minister Sanae Takaichi. She said last week that a Chinese attack on Taiwan could amount to a "survival-threatening situation", potentially triggering a military response from Tokyo.

Kihara said Japan and China differ on the issue and it was vital to maintain communication, Kyodo reported.

China claims democratically governed Taiwan and has not ruled out using force to take control of the island, which sits just 110 km (70 miles) from Japanese territory. Taiwan's government rejects Beijing's sovereignty claims.

Japanese leaders have previously avoided publicly mentioning Taiwan when discussing such scenarios, maintaining a "strategic ambiguity" also favoured by Tokyo's main security ally, the United States.