South Korea and Japan both confirmed on Saturday that North Korea had fired a ballistic missile that travelled across waters to the country's east, adding to a series of similar launches recorded throughout the year. The launch came a day after Pyongyang rejected Seoul's assertion that landmines of North Korean origin had wounded soldiers.

According to a statement from the South Korean military, the projectile lifted off from near Wonsan at approximately 6:30 in the morning on Saturday, covering a distance in excess of 700 kilometres before coming down. Analysts at both locations examined the flight data in an effort to draw conclusions about what the test had demonstrated.

An advisory issued by the coast guard, citing the defence ministry, indicated that an object believed to be a ballistic missile had descended and urged vessels in the area to exercise caution. Armed forces officials announced they had stepped up surveillance of potential additional missile launches, with findings to be shared with allied partners in Washington and Tokyo.

A gathering of the presidential office's national security council took place on Saturday to evaluate developments following the missile launch, according to a statement released by the office.

North Korea has conducted ballistic missile tests on more than ten separate occasions during the current calendar year. On occasion, the North Korean government has described its activities as trials of new categories of weaponry. A portion of those weapons tests have followed instances in which North Korea raised objections to joint military exercises conducted by Seoul and Washington.

The launch followed a statement issued Friday by Kim Yo Jong — the sister of Kim Jong Un and a figure who holds considerable influence within North Korea's leadership — in which she rejected Seoul's call for an apology over what South Korean authorities described as North Korean mines that had wounded its soldiers inside the Demilitarised Zone, the fortified strip of land dividing the peninsula.

Two soldiers on patrol inside the buffer strip — a corridor roughly four kilometres across that runs the length of the Korean Peninsula — sustained wounds from landmines, with South Korean authorities announcing in recent days that the devices were placed there by North Korea.

Cheong Seong-chang, vice president at the Sejong Institute, a Seoul-based organisation focused on North Korean affairs, said the launch may have been intended to provoke a reaction from South Korea in response to the statement by Kim Jong Un's sister. He also noted that the country may have tested a previously unseen category of missile.

North Korea has, across the past several years, formally repositioned South Korea as its primary declared enemy while stepping back from reunification as a policy goal.