The two sides have been at loggerheads since Japan's Prime Minister Sanae Takaichi suggested her country could intervene militarily if Taiwan -- which Beijing claims as part of its territory -- were to be attacked.

As the disagreement escalated, China late Friday issued a warning to citizens to avoid travel to Japan for the foreseeable future.

That warning has had a dramatic effect, said independent aviation analyst Li Hanming, who has compiled daily data on Chinese passengers' active flight bookings from major airlines and online travel agencies since 2023.

According to his data, active bookings to Japan dropped from around 1.5 million on November 15 to just one million two days later, leading Li to conclude that around 500,000 trips had been cancelled.

Since he has started his database, active ticket bookings normally drop by around five percent on a day-to-day basis, he told AFP -- a stark contrast to the 33 percent plunge observed between those dates.

"There will definitely be more cancellations if the tensions intensify," Li said.

Several Chinese airlines, including its three largest, have offered full refunds for flights to Japan booked until December 31.

China-based travel agencies had mixed reactions to the travel advice when contacted by AFP on Tuesday.

One large state-owned tourism company had removed all Japan travel options from its app, while another Beijing-based agency said it was no longer accepting Japan bookings.

Others contacted by AFP said their Japan tours were still operating as normal and expressed hope that the disruption would be temporary.

Chinese tourists are the largest source of visitors to Japan, with almost 7.5 million visiting in the first nine months of 2025 according to Japanese figures.

They collectively splurged more than a billion dollars a month in the third quarter, accounting for almost 30 percent of all tourist spending.

Japanese tourism and retail shares dived on Monday after China's travel warning.