South Korea asserted that Japan must gain prior consent from Seoul before launching any military operations in North Korea during recent bilateral talks, but Tokyo has refused to agree on whether it needs permission, a Defense Ministry official said Wednesday.

Whether Japan would agree to seek Seoul's consent before engaging in any military operations in North Korea had been the focus of attention as Tokyo is moving to strengthen its military power in the Asian region. 

The World War II aggressor has recently enacted new security laws allowing its self-defense forces to fight in an overseas war under the right to collective self-defense.

Japan has assured that it will not be involved in any military action in South Korea without consent from the South on several occasions, including talks between the two countries' defense ministers, Han Min-koo and Gen Nakatani, held on Tuesday in Seoul.

Constitutionally, South Korea considers North Korea's territory as part of its domain.

During the defense talks, the South Korean side tried to get Japan's affirmation on the issue, but Nakatani did not agree, the official said in a background briefing earlier in the day.

"There are some opinions that the scope of South Korea's effective control is below the truce line," the official quoted the Japanese defense minister as saying. Instead, Nakatani left the issue open for more discussion with the United States, saying it needs "close collaboration among South Korea, the U.S. and Japan," according to the official.

The opposing remarks by Nakatani were not released in the Defense Ministry's press briefing on the talks Tuesday and became known to the public through Japanese news reports.

The differing stances highlight South Korea's security concerns over Japan's growing military presence in the Asian region at a time when North Korea's nuclear and missile threats are fast advancing. (Yonhap)