South Korea's international air passenger traffic jumped more than 20 percent in May from a year earlier on higher demand for air travel, government data showed Wednesday.

The number of international travelers to and from South Korea soared 21.3 percent on-year to 5.44 million, according to the data compiled by the Ministry of Land, Infrastructure and Transport.

The country's overall air passenger traffic spiked 23.9 percent to 8.03 million, with the number of domestic passengers also surging 29.6 percent to 2.59 million.

Visitors from China soared 28 percent to 1.69 million over the cited period, due largely to increased flights connecting South Korea with the world's most populous nation.

A weaker Japanese currency, as well as global oil prices, also led to a 22 percent on-year increase in air passengers on South Korea-Japan routes, reaching 1 million in May, according to the data.

Domestic flight travelers visiting the southern resort island of Jeju surged 36.1 percent on-year to 1.12 million, as the region continues to be one of the favorite tourist destinations among both locals and foreigners.

In contrast to the May rise, air passenger traffic has tumbled in June in the wake of the Middle East Respiratory Syndrome (MERS) outbreak in South Korea.

The overall number of air travelers plunged 19.5 percent on-year in the first three weeks of June, with the drop in international air passenger traffic hovering at around 20 percent since June 16, according to ministry data.

Furthermore, South Korea's top air carriers -- Korean Air Lines Co. and Asiana Airlines Inc. -- have scaled back their flights mostly to and from China to cope with the decline in passengers, with the number of international flights forecast to drop by around 1,700 flights on-year in the June-July period. 

As of Wednesday morning, the total number of people diagnosed with the respiratory disease came to 179 and the MERS-related death toll stood at 27, according to the Ministry of Health and Welfare. (Yonhap)