North Korea fired a short-range ballistic missile that landed in Japan's maritime economic zone Monday, officials said, the latest in a string of test launches as the North seeks to build nuclear-tipped ICBMs that can reach the US mainland.
South Korea's military said what appeared to be a new Scud missile flew 280 miles.
Japan lodged a protest against the North's latest missile launch, which appeared to have landed in Japan's exclusive economic zone.
In Washington, a National Security Council spokesman said the USA government was aware of reports of a projectile launch, adding that "the president has been briefed".
North Korea, which has conducted dozens of missile tests and tested two nuclear bombs since the start of 2016 in defiance of U.N. Security Council resolutions, says the programme is necessary to counter US aggression.
North Korea is still thought to be several years from its goal of being able to target USA mainland cities with a nuclear intercontinental ballistic missile. "Working with the United States, we will take specific action to deter North Korea".
The test was leader Kim Jong un's third in three weeks. It wasn't clear from the state media report when the test happened.
Kim found that the weapon system's ability to detect and track targets had "remarkably" improved and was more accurate, according to the official Korean Central News Agency.More news: May's Conservatives maintain 14-point lead over Labour: ICM poll
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"Expressing his satisfaction, Kim said: "(It) should be mass-produced to deploy in all over the country like forests so as to completely spoil the enemy's wild dream to command the air, boasting of air supremacy and weapon almighty".
The launch comes despite tough talk from US President Donald Trump, who promised last week at the G7 summit that the "big problem" of North Korea "will be solved".
"The North Korean regime has hundreds of artillery cannons and rocket launchers within range of one of the most densely populated cities on Earth, which is the capital of South Korea", he told CBS News. But many analysts say Moon won't likely push for any major rapprochement projects because North Korea has gone too far on its nuclear program.
South Korea's Moon swiftly called a meeting of the National Security Council, South Korea's Office of the Joint Chiefs of Staff said in a statement.
Japanese Prime Minister Shinzo Abe told reporters that "North Korea's provocation by ignoring repeated warnings from the worldwide society is absolutely unacceptable". "The situation on the Korean peninsula is complex and sensitive, and we hope all relevant sides maintain calm and exercise restraint", China's foreign ministry said in a statement.
The North has carried out two atomic tests and dozens of rocket firings since the beginning of past year in its quest to develop a missile capable of delivering a nuclear warhead to the continental United States.
North Korea has been stepping up efforts towards its ultimate goal - developing an intercontinental ballistic missile that can deliver a nuclear warhead to the continental US.
Seoul recently said it will allow a civic group to contact North Korea about helping them treat malaria, which marks the first government-approved cross-border civilian exchange since January 2016.