BEIJING, Jan 26 (Reuters) - China on Monday warned its citizens against travelling to Japan during the Lunar New Year, its longest public holiday, as Beijing's anger over a comment Japanese Prime Minister Sanae Takaichi made in early November about democratically governed Taiwan showed no signs of abating.

Japan underlined their dominance in Asian youth football with a commanding victory over China in the U23 Asian Cup final, defending their continental title and becoming the first team to win the tournament three times.

China warned its citizens on Monday against travelling to Japan during the upcoming Lunar New Year holiday, citing deteriorating public security, with Tokyo and Beijing locked in a diplomatic spat.

Beijing warns citizens against visiting ahead of Lunar New Year holiday as airlines extend deadline for refunds or flight changes.

Japan’s diplomatic mission in the southwestern Chinese megacity of Chongqing has been left without a consul-general, as relations between Tokyo and Beijing remain strained.

Chinese football faces its biggest match in more than 20 years on Saturday when it plays Japan in the final of the Under-23 Asian Cup in Jeddah, Saudi Arabia.

The number of Chinese visitors to Japan plummeted by 45 per cent last month from a year earlier, to around 330,000.

The number of Chinese visitors to Japan plummeted by 45% last month from a year earlier, to around 330,000, as a result of the spat.

CNBC's China reporter Elaine Yu chats with Squawk Box Asia anchors Martin Soong and Chery Kang about the so-called "panda diplomacy", as Japan is due to return two pandas to China amid rising tensions.