Korean airlines are no longer allowed to share routes for their nonregular flights to China after the Chinese aviation authorities decided to allocate only one route per air carrier for unscheduled flights.

The Ministry of Land, Infrastructure and Transport said Sunday that it has recently adjusted the number of nonregular flights to China that are operated by seven local airlines from the previous 365 to 311 to meet the regulations.

The adjustment was carried out voluntarily by airlines, but the ministry said it had to mediate some cases where companies failed to reach an agreement.

In September, the budget carrier Eastar Jet secured the most nonregular flights at 85, while Asiana Airlines and Korean Air were allocated 70 and 53 flights, respectively.

Under the new rules, a nonregular route is allocated to only one carrier for a specific period ― less than four months ― and its operation is also limited to twice per week.

According to industry watchers, the toughened measure comes as the Chinese government aims to protect regular routes operated by local airlines while limiting the number of nonregular services by foreign competitors.

On July 26, Jeju Air, a low-cost airline, cancelled its nonregular flight to Sanya on Hainan Island just a few hours before the departure, as the Chinese authorities rejected the route.

The ministry said it plans to encourage airlines to adjust their number of nonregular flights voluntarily from October while persuading the Chinese authorities to ease the regulations.

By Lee Ji-yoon (jylee@heraldcorp.com)