International flights to and from China are expected to increase nearly 31% year-on-year between late October and March, with Asian destinations and Chinese carriers leading the way, industry data shows.

A Canadian airline also expanded so sharply that it attracted the attention of the Foreign Ministry in Beijing.

One-way flights to and from China are expected to rise by almost 40,000 to 168,871 between the end of October and March from a year earlier, according to data compiled by British aviation analytics firm OAG.

The number of seats on offer could also increase by 29 percent to 35.2 million, according to OAG data.

“In general, tourism is the most important factor,” said Li Hanming, founder of a U.S.-based aviation consultancy.

“It’s winter now, so people from northern China are flying south.”