"An increase in travel demand on routes to and from Japan and Southeast Asian countries helped offset sharp declines in demand on Chinese routes last month," the ministry said in a statement.

The number of passengers on Chinese routes fell 47 percent year-over-year to 897,474 last month, while that of passengers on the Japanese and Southeast Asian routes declined 30 percent and 24 percent, respectively, compared with a year earlier, the statement said.

Starting March 15, China banned the sales of group travel packages to South Korea as part of its apparent retaliation against the installation of the Terminal High Altitude Area Defense system.

Seoul and Washington have argued the THAAD system is purely aimed at countering missile threats from North Korea. But Beijing has opposed the system, arguing it could be used against it.

Meanwhile, the country's air cargo traffic also rose 6.6 percent to 353,063 tons in April from 331,293 tons a year earlier, the statement said.

"An increase in exports of semiconductors and other information-technology products pushed up the monthly cargo traffic," it said. (Yonhap)