North Korea slammed South Korea on Saturday for making critical comments on a Japanese official’s recent visit to Pyongyang, calling it an “unprecedented precipitancy.”

Isao Lijima, an adviser to Japanese Prime Minister Shinzo Abe, returned to Tokyo Friday after a surprise four-day visit to North Korea. In Pyongyang, he met with high-ranking officials, including Kim Yong-nam, president of the Presidium of the Supreme People‘s Assembly.

Little has been known about the purpose of Lijima’s trip, but the two sides reportedly discussed  wide-ranging issues of mutual interest, including ways to resolve ongoing disputes over the abduction of about a dozen Japanese nationals by North Korea decades ago.

The abduction issue, along with the North‘s demand for compensation for Japan’s colonial rule of North Korea in the early part of the 20th century, is a major pending issue between the two countries.

Japan normalized with South Korea in 1965 but has no formalties with North Korea.  

South Korea has taken a critical stand on Lijima‘s trip, expressing concern that it may hurt international efforts to form a unified approach to the belligerent North Korea which remains under U.N. sanctions for its missile and nuclear weapons programs.

“It is important to maintain a close coordination, among South Korea, the U.S. and Japan, toward North Korea,” South Korean Foreign Ministry Spokesman Cho Tai-young told reporters on Thursday. “In that sense, we think that the visit by Iijima to North Korea is unhelpful.”

North Korea showed anger at the South Korean stance.

“Officials’ trip between countries is just common on the international arena. It is not a matter of intervention by a third party,” the North said in a statement posted on its main propaganda Website, Uriminzokkiri.

Lijima‘s trip drew attention from Washington as well. U.S. and South Korean officials said they were not informed of his trip in advance.

Lijima is said to have helped arrange former Japanese Prime Minister Junichiro Koizumi’s trips to Pyongyang for talks with then North Korean leader Kim Jong-il in 2002 and 2004.

During Lijima‘s 2002 trip, Kim admitted that North Korean agents had kidnapped a total of 13 Japanese citizens to use them as language instructors for communist spies.

North Korea then allowed eight of those Japanese abductees to return home but said the five others died of infectious diseases or killed in traffic accidents. Japan discredited the North’s explanations, insisting that some of them may still be alive. (Yonhap News)