Mainland authorities on Wednesday said they will increase capacity during the upcoming Spring Festival travel rush, which is expected to be the busiest ever.

The 40-day period, also known as "Chunyun" season, will run from January 14 to February 22, with the Year of the Snake starting on January 29.

Authorities expect the number of inter-regional trips to hit 9 billion, and rail and flight passenger trips to exceed 510 million and 90 million respectively, all record highs.

"The scale of the Spring Festival travel rush will further increase this year. It's also the first year that Lunar New Year's Eve is a national holiday, so there will be eight days off in total during the Spring Festival," Li Chunlin, deputy director of the National Development and Reform Commission (NDRC), told a press conference in Beijing.

"Passenger flows will be higher before and after the holiday, and the NDRC and other bodies have conducted early research and planning. We'll adopt comprehensive measures to try our best to meet the demands of the public."

To accommodate higher passenger flows, Li said more than 140,000 railway trains will be arranged on average each day during the travel rush, up 4 percent year on year, while the daily number of flights will be about 185,000, up 8.4 percent from last year.

The official also said passenger flows will be particularly high in the Beijing-Tianjin-Hebei regions, as well as in Guangdong, Hong Kong and Macau.

The number of road trips, meanwhile, is projected to reach 7.2 billion, accounting for about 80 percent of the total, and daily highway traffic could also hit a record high.