The US will not relent until it achieves its objective of ensuring the Korean Peninsula is free of nuclear weapons, Vice President Mike Pence has said while visiting Japan.
North Korea's deputy United Nations ambassador has accused the United States of turning the Korean Peninsula into "the world's biggest hotspot" and creating "a dangerous situation in which a thermonuclear war may break out at any moment".
North Korea has fired a ballistic missile into the waters off its east coast, US and South Korean officials said, amid worries that Pyongyang might soon conduct banned nuclear or long-range rocket tests.
The United States has rejected China's proposal for a halt to joint US-South Korean military exercises if North Korea suspends its nuclear and missile activities.
China has proposed that North Korea suspend its nuclear and missile activities in exchange for a halt in joint military drills conducted by the US and South Korea.
LATEST: An arrest warrant has been issued for a North Korean airline employee over the fatal poisoning of the half-brother of North Korea's leader, Malaysian police said.
North Korea has condemned the start of US-South Korean military drills with fiery rhetoric which was given added weight by recent missile and nuclear tests by Pyongyang.
Two women accused of killing the half-brother of North Korea's leader with a nerve agent in a Kuala Lumpur airport terminal will be charged with murder on Wednesday, Malaysia's chief prosecutor has said.
North Korea has executed five senior security officials for making false reports to leader Kim Jong Un, according to South Korea's intelligence agency.
A dispute over custody of the body of North Korean leader Kim Jong Un's half-brother is raging between Malaysia and Pyongyang as inquiries continue into his apparent assassination.
Latest: Malaysian police say they have arrested a woman in connection with the death of North Korean leader Kim Jong Un's half-brother.
The United States, Japan and South Korea have asked for an urgent meeting of the United Nations Security Council on North Korea's ballistic missile launch.