On Tuesday, President Yoon Suk Yeol backed a proposal for a "complete suspension" of the comprehensive military accord in response to the North's trash-carrying balloon campaign and GPS jamming attacks in recent days, Yonhap news agency reported.

The move enables South Korea to resume drills to strengthen frontline security. Previously, artillery and naval exercises, as well as regimental-level field maneuvers, were banned due to the land and sea buffer zones established in the area. No-fly zones were also designated near the border to prevent accidental aircraft collisions.

Marine Corps troops stationed in the Northwest Frontier islands are planning to conduct firing practice with K-9 self-propelled howitzers for the first time in nearly six years, sources said.

With the exception of a live-fire exercise conducted in January in response to artillery shells fired by the North near the two South Korean western border islands of Yeonpyeong and Byungnyeong, the military had avoided conducting artillery exercises in the area.

The Army is also expected to resume artillery practice at three shooting ranges located in areas already designated as land buffer zones.

An Army official said front-line units maintain readiness to conduct artillery exercises at facilities once training plans are established.

North Korea has stepped up artillery drills involving K-9 howitzers in the border area, raising concerns over rising military tensions near the Northern Demarcation Line in the Yellow Sea, the de facto western maritime border between the two Koreas.

In 2010, the North bombed the border island of Yeonpyeong, killing two civilians and two marines.