If it ends up doing so, leading to complete suspension of dialogue between the United States and North next year, "we could look back and see these missile launches as a new chapter of North Korea's provocation cycle", Go said.
"But it is also worth noting that Pyongyang has emphasized the word "tactical" in the name of the weapon, which means it is not a long-range missile that poses a threat to the USA mainland", Zhang added.
And in a potential indication of more launches to come, KCNA said that Kim "set forth important tasks for further increasing the strike ability of the defence units".
The North "will keep increasing pressure and every next step will be more and more serious", said Professor Andrei Lankov of Kookmin University.
Kusong is also home to missile test facilities that were critical to the development of North Korea's solid-fuel Pukguksong-2, which was successfully flight-tested for the first time in February 2017, in the North's first missile test after President Donald Trump took office.
If Thursday's launch proved to be a ballistic missile, Moon said, even if it was short-range, "it has a possibility of running foul of United Nations resolutions". The ship also delivered heavy machinery back to North Korea.
The missile launch is likely to be a protest against the US for refusing to ease sanctions at the failed Hanoi summit between Trump and Kim Jong Un in February.
From the U.S. side, participants were Alex Wong, U.S. deputy assistant secretary of state for DPRK affairs, and Allison Hooker, director of the White House National Security Council for the DPRK.
A separate statement by a North Korean foreign ministry spokesman described the launches as a "routine and self-defensive military drill".
Japanese Prime Minister Shinzo Abe wants to meet North Korean leader Kim Jong-un without conditions to resolve mutual mistrust and sort out ongoing bilateral issues, a government spokesperson said on Tuesday.
By firing weapons that directly threaten South Korea but not the USA mainland or its Pacific territories, North Korea also appears to be testing how far Washington will tolerate its bellicosity without actually causing the nuclear negotiations to collapse, Cha said.
North Korea says the test was part of its regular military training.
"I don't think we should get too excited about a short-range test unless someone can tell us that it was a long-range test that failed", Ganyard said.
The South's military is analyzing the short-range launch, North Korea's second in less than a week.
The launch came as U.S. special envoy for North Korea Stephen Biegun was in Seoul for talks with South Korean officials.
The Iskander missiles have always been a source of tension in Europe and were cited by President Donald Trump as a key reason behind his decision in February to break with the 1987 Intermediate-Range Nuclear Forces Treaty, which bans production, testing and deployment of land-based cruise and ballistic missiles with a range of 500 to 5,500 kilometers (310 to 3,410 miles).
Meanwhile, North Korea has pushed ahead with its weapons program, with leader Kim Jong Un overseeing the test-firing of a new "tactical guided weapon" in mid-April.