US President Donald Trump downplayed on Friday North Korea's missile tests, saying that while they may violate a United Nations resolution, Kim Jong Un will not want to "disappoint" him because he has "too much to lose". "We never made an agreement on that".
The string of tests are being seen as reaction to planned military exercises between South Korea and the US.
North Korean state media has described the weapons as a new large-calibre, multiple-launch guided rocket system and said Kim oversaw the previous launch on Wednesday.
It conducted a similar short-range missile launch earlier in May, its first such test since its intercontinental ballistic missile launch in 2017.
Nuclear-armed North Korea is barred from ballistic missile tests under United Nations resolutions.
North Korea's leader Kim Jong Un (right) walks with President Donald Trump during a break in talks at their historic US-North Korea summit, at the Capella Hotel on Sentosa island in Singapore, June 12, 2018. We never discussed that.
North Korea has signalled that further denuclearization talks could be derailed by the refusal to scrap the annual maneuvers, describing last week's launch as a "solemn warning to the South Korean warmongers".
"We are monitoring the situation in case of additional launches and maintaining a readiness posture", South Korea's Yonhap news agency quoted the country's joint chiefs of staff as saying.
There are 28,500 USA troops stationed in South Korea to protect it against its nuclear-armed neighbor, many of them based south of Seoul at Camp Humphreys in Pyeongtaek.
The Japanese Ministry of Defence said on Friday no immediate impact was seen on Japan's security after North Korea's latest launch.
Earlier on Thursday, U.S. national security adviser John Bolton told Fox Business Network that the launches since last week did not violate Kim's pledge not to test long-range missiles or nuclear bombs.
Despite Trump's words, North Korea has embarrassed the USA president by testing the missiles even though he and Kim agreed at a June 30 meeting to revive stalled denuclearization talks.
"We won't be defeated by Japan again", Moon told his cabinet, pointedly invoking South Korea's hard history with Japan, which colonized the Korean peninsula before World War Two. North Korea also has expressed frustration at planned U.S. "We're ready for working-level negotiations".
A summit between Trump and Kim in Vietnam in February collapsed after the two sides failed to reconcile differences between US demands for North Korea's complete denuclearization and North Korean demands for sanctions relief.
South Korean officials have held a different perspective, particularly since last month, when Japan tightened curbs on exports to South Korea of three high-tech materials needed to make memory chips and display panels, threatening the global supply of chips.
Upon implementation, South Korea would be the first country to be removed from Japan's white list, which now includes 27 countries including Germany, Britain and the US, reports Reuters.
The North Korean launches have appeared meant to put pressure on South Korea and the United States to stop planned military exercises this month and offer other concessions.
Trump said on Thursday he wasn't anxious about the weapons recently tested by North Korea, calling them "short-range missiles" that were "very standard".
The North Korean statement accused the U.N. Security Council of "groundlessly slandering" Pyongyang's development of conventional weaponry "while turning blind eyes to the war exercises in south Korea and shipment of cutting-edge attack weapons into it".
U.S. Secretary of State Mike Pompeo said on Thursday he hoped the two would find a solution by themselves, stressing cooperation on North Korea was "incredibly important".
Some analysts believe Kim will have been emboldened to press more aggressively for concessions given Trump's apparent eagerness to hold up his North Korea policy as a success in his 2020 re-election bid.
The three countries also urged North Korea "to take concrete steps toward its complete, verifiable and irreversible denuclearization" and said worldwide sanctions should remain in place and be fully enforced until its nuclear and ballistic missile programs are dismantled.