North Korea's military staged a "large-scale artillery drill" around the Wonsan region in the country's east on Tuesday, a statement from the South Korean military said.
The report, citing an unidentified government source, said the live-fire exercise was possibly supervised by North Korean leader Kim Jong Un.
The diplomats are Kenji Kanasugi, director general of the Japanese Foreign Ministry's Asian and Oceanian Affairs Bureau; Joseph Yun, U.S. special representative for North Korea policy; and Kim Hong Kyun, South Korea's special representative for Korean Peninsula peace and security affairs.
A U.S. guided-missile submarine arrived in South Korea on Tuesday and envoys from the U.S., Japan and South Korea met in Tokyo, as North Korea prepared to mark the anniversary of the founding of its military.
Speculation has been rife that Pyongyang may conduct its sixth nuclear test or launch a long-range ballistic missile to mark its military event.
Earlier this month, President Donald Trump had said that the USA was sending an "armada" with submarines to the region.
"Pyongyang must not strike a match and detonate it". Pretty much the entire world is freaked out today over the possibility of future nuclear tests (or worse) by "that gentleman" in Pyongyang, as forgetful Donald likes to call him.
Adding to the atmosphere of animosity, officials said North Korea has detained a third USA citizen. She praised China's increased pressure on North Korea.More news: The Ford Mustang is the best-selling sports car in the world
At a "national meeting" of thousands of senior military and civilian officials the day before, North Korea's Minister of Defense Gen. Pak Yong Sik reiterated that the country is ready to use pre-emptive strikes or any other measures it deems necessary to defend itself against the "U.S. imperialists". Despite deepening tensions on the Korean Peninsula, residents of the North korean cap. Those ties have frayed, but Beijing remains the North's economic lifeline.
Mr Trump spoke by phone with both the Japanese and Chinese leaders yesterday.
South Korea's Office of the Joint Chiefs of Staff said in a brief statement that the North Korean exercise was under way on Tuesday afternoon.
He said the planned April 28 meeting of the U.N. Security Council will be a pivotal venue for the ultimate achievement of the complete, verifiable and irreversible dismantlement of the North Korean nuclear program.
Kim Jong Un's regime marked the 85th anniversary of the founding of North Korea's army Tuesday with its typical bluster.
The US navy strike group including the aircraft carrier Carl Vinson is expected to arrive near the Korean Peninsula later this week, a move seen as countering Pyongyang's possible provocations. But the ships are probably several days from arriving in the region.
US President Donald Trump has called on the UN Security Council to impose new and stronger sanctions on North Korea.
Talking to fifteen UN Security Council ambassadors, including those of China and Russian Federation, at the White House, he said the status quo in North Korea is unacceptable. It further questioned whether Trump has "entirely left out South Korea in his picture for the Korean Peninsula". "And it's a problem we have to finally solve".More news: Marissa Mayer Is Leaving Yahoo with an Insane Amount of Money
The comments are sure to once again ratchet up tensions.
North Korea is pushing on with its ballistic missile program, believed to be preparing a sixth nuclear weapons test, and has detained a U.S. citizen - the third to be held in the country.
At the same time, the United States has ordered an aircraft carrier strike group to the western Pacific, near North Korea.
A U.S. Air Force U-2 spy plane prepares to land at Osan Air Base in Pyeongtaek, South Korea, Tuesday, April 25, 2017.
"This is a real threat to the world, whether we want to talk about it or not".
As well as his military show of force, Trump has also sought to pressure China to do more to rein in its nuclear-armed neighbor.
On Monday, Trump called for tougher United Nations sanctions on the North, saying it was a global threat and "a problem that we have to finally solve".More news: German Company Acquires Akorn Inc
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