North Korea says missile test was 'stern warning to South Korean warmongers'

North Korean leader Kim Jong Un watches a missile test. Photo / AP

North Korea said its test of a "new type of tactical guided weapon," overseen by leader Kim Jong Un, was a demonstration of its power, and a direct warning to "South Korean military warmongers" - a declaration that underlines how relations between the two Koreas are again deteriorating and tensions rising.

The Korean Central News Agency said the launch was a response to joint U.S.-South Korea military exercises, as well as South Korea's own introduction of "ultramodern offensive weapons." It said Kim had vowed to continue to develop and test North Korea's own weapons systems in direct response.

Experts said it was almost certainly a reference to South Korea's imports of F-35A stealth fighter jets from the United States, a move Pyongyang has denounced as "extremely dangerous."

North Korea's missile launches rattled Asia this week. Photo / AP

South Korea described Thursday's launch as a new type of short-range ballistic missile, saying one had flown about 418km and the other 692km.

That followed a similar test of short-range ballistic missiles in May, and would be a clear violation of United Nations Security Council resolutions, as well as a direct threat to South Korea and U.S. forces there, experts said.

Kim personally guided and supervised Thursday's launch, KCNA said, "as part of the power demonstration to send a solemn warning to the South Korean military warmongers," who it said are "running high fever" by importing new weapons and holding military exercises "in defiance of the repeated warnings" by North Korea.

A U.S. F-35A fighter jet prepares to land at Chungju Air Base in Chungju, South Korea. North Korea slammed South Korea for introducing high-tech U.S. stealth fighters. Photo / AP

Earlier this month, North Korea also warned that planned military exercises involving U.S. and South Korean forces would jeopardize proposed disarmament talks with Washington, and it hinted that it might respond by resuming nuclear and missile tests. It accused President Donald Trump of reneging on a commitment to suspend the exercises.

Kim had mounted an observation post to guide the successful weapons tests, KCNA reported. "And it must have given uneasiness and agony to some targeted forces enough as it intended."

Kim said the new tactical guided weapon, with a low altitude and "leaping flight," would be hard to detect, calling it "of huge eventful significance in developing our armed forces and guaranteeing the security of the country by military force."

A North Korean test of a new-type tactical guided weapon was meant to be a "solemn warning" about South Korean weapons introduction. Photo / AP

While Trump repeatedly sought to play down North Korea's last short-range ballistic missile test in May, experts said the new missiles are a direct threat to Seoul, capable of carrying both nuclear and conventional warheads and designed to fly low enough to potentially avoid detection and interception by South Korea's THAAD and Patriot missile defense systems.

"Being road mobile, North Korea can increase survivability of its missiles by continuously moving them, hiding them in tunnels, warehouses, and even highway underpasses," said Duyeon Kim at the Center for a New American Security. "If these are an Iskander-style missile, then they could have jet vanes, which means it can be maneuvered during its ballistic trajectory making it difficult to predict where the missile will land and intercept it before it does."

North Korean leader Kim Jong Un watches a missile test. Photo / AP

South Korea had also underplayed May's missile test, in an apparent attempt not to derail the delicate state of talks, but on Thursday, it acknowledged that North Korea had tested ballistic missiles.

Kim said North Korea was determined to counter South Korea's introduction of offensive weapons, which he called "suicidal" and a direct threat to the North, and said he was determined to steadily develop and test the North's own weapons in response.

"The south Korean chief executive should not make a mistake of ignoring the warning from Pyongyang, however offending it may be," KCNA said.