At least 12 cross-border air routes between China and Japan have cancelled scheduled flights as of 10 am on Monday, financial media outlet Yicai reported, citing data from online aviation tracker DAST.

Data from DAST shows that the cancellation rate for flights to Japan is set to rise steadily over the coming week, with the cancellation rate projected to reach 21.6 percent on Thursday, the highest in a month.

Routes experiencing the highest cancellation ratios include Tianjin Binhai–Kansai International in Osaka at 65 percent, Nanjing Lukou–Kansai at 59.4 percent, Guangzhou Baiyun–Kansai at 31.3 percent, and Shanghai Pudong–Kansai at 30.1 percent, according to the report.

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Neither airlines nor regulators have publicly commented on the reasons behind the rising cancellations, and it remains unclear whether this trend will continue into January.