South Korea says it worked closely with US following delayed disclosure of North Korea missile launch

South Korea said on Monday that it is maintaining close coordination with the United States on North Korea's missile launches, after criticism arose over its delayed announcement of the North's latest launch.

The North's state media said Friday that North Korea conducted tests of a new multiple rocket launcher and other key weapons the previous day, a launch that was overseen by its leader Kim Jong-un.

South Korea's Joint Chiefs of Staff (JCS), however, did not disclose details of the latest launch on the day of the test-firing, raising the question of whether it withheld the information or failed to detect the weapons launch in time.

A local media outlet raised the possibility that the US' decision to limit information-sharing with South Korea on the North's military movements may have hampered Seoul's ability to track them in real time.

"South Korea and the US detected and tracked in real time multiple projectiles launched by North Korea between 7:27 a.m. and 8.20 a.m. on June 25, maintaining close coordination for all contingencies," Col. Lee Kyung-ho, deputy defense ministry spokesperson, said in a press briefing.

Lee said the projectiles are classified as "tactical weapons systems" and detailed specifications will be finalized after a comprehensive analysis.

"The bilateral information-sharing and coordination mechanism (with the US) remains seamless and our military maintains a 24-hour watertight readiness posture," he said.

"We ask (people) not to undermine the dedication of South Korean and US service members, who are devoted to defending the Republic of Korea and ensuring the safety of our citizens, through political interpretations," Lee added.

The JCS discloses North Korea's missile launches when they involve a test-firing of ballistic missiles in violation of UN Security Council resolutions, Yonhap news agency reported.

North Korea's latest tests involved an upgraded version of the 240mm-caliber 24-tubular multiple rocket launcher system, "special mission" warheads for tactical ballistic missiles and the extended-range shells for a 155mm self-propelled howitzer, according to its state media.