The US Defence Department has confirmed that North Korea carried out a missile test, and said the launch failed "almost immediately".
Security will nearly certainly be a key point in discussions with Japan's Prime Minister, Shinzo Abe, who said Thursday that North Korea may now may have the capability to deliver missiles equipped with sarin nerve gas.
North Korea's vice foreign minister says, "We will go to war" if the USA chooses to provoke it.
A North Korean missile "blew up nearly immediately" on its test launch on Sunday, the U.S. Pacific Command said, hours before U.S. Vice President Mike Pence was due in South Korea for talks on the North's increasingly defiant arms programme.
"The launch of the ballistic missile occurred near Sinpo", US Pacific Command spokesman CDR Dave Benham said. His national security adviser, H.R. McMaster, said the US would rely on its allies as well as on Chinese leadership to resolve the issues with North Korea.
The US has sent a nuclear-powered aircraft carrier to the peninusla as North Korea today marks the 105th anninversary of the birth of its founder Kim Il Sung today.
The US president also flexed his military muscle last week by ordering cruise missile strikes on a Syrian airbase the US believed was the origin of a chemical weapons attack on civilians in a northern Syria town.
Aside from improving the technology, North Korean missile and nuclear tests are seen by outside analysts partly as efforts to bolster the domestic image of leader Kim Jong Un and apply political pressure on Seoul and Washington.
"This morning's provocation from the North is just the latest reminder of the risks each one of you face every day in the defense of the freedom of the people of South Korea and the defense of America in this part of the world", he told members of the U.S. military in South Korea. The adviser spoke on condition of anonymity to discuss the administration's initial understanding of the launch. "Our military is building and is rapidly becoming stronger than ever before", he tweeted. Obviously, we've been working here collaboratively with the National Security Council, again, to look for a wide range of options for North Korea, one of which, to no surprise, would be sanctions.
US, China Working On North Korea Problem
Deputy national adviser K.T. McFarland briefed the president on the failed missile launch.
"North Korea is a liability to everybody and it's a threat not just to the United States, not just to South Korea, not just to Japan, not just to Russian Federation, but it's actually a threat to China as well", McFarland said Sunday on "Fox News Sunday".
The attempted launch came as US Vice President Mike Pence arrived in Seoul on Sunday as part of a four-day tour of the region.
In a statement on official news agency KCNA, the North's Korean People's Army said Trump had "entered the path of open threat and blackmail against the DPRK".
Along with the deployment of the US aircraft carrier and other vessels into waters off the Korean Peninsula, thousands of USA and South Korean troops, tanks and other weaponry were deployed last month in their biggest joint military exercises.
North Korea's vice foreign minister says it will conduct its next nuclear test whenever its supreme headquarters sees fit. The US may hit North Korean missiles if they're launched, and Pyongyang will deliver a tough diplomatic response.
U.S. Vice President Mike Pence visits with troops at Camp Bonifas, just south of the DMZ.
Outside experts say the North could conduct its sixth nuclear test at virtually anytime.