The United States and South Korea are set to begin joint military exercises in the Sea of Japan on Monday, with the participation of a nuclear-powered US aircraft carrier.
The drills, involving a strike group led by the USS Ronald Reagan, will continue through Thursday.
The US highlighted the carrier's deployment near the Korean Peninsula as part of its efforts to boost deterrence against North Korea in a meeting of senior foreign and defense officials from Washington and Seoul earlier this month.
The South Korean government stressed that Seoul and Washington will strengthen their joint defense capabilities and reconfirm their strong resolve to neutralize any forms of missile provocations by Pyongyang.
North Korea criticized South Korea for working with the US to beef up deterrence. Pyongyang said on a state-run website on Sunday that plots for war provocations will only create dreadful destruction.
North Korea on the same day launched a short-range ballistic missile toward the Sea of Japan from an area in or around Taechon, North Phyongan Province. The missile is estimated to have landed outside Japan's exclusive economic zone.
North Korea also appears to be preparing to fire a submarine-launched ballistic missile, or SLBM, in the city of Sinpho in the eastern province of South Hamgyong.
Washington and Seoul remain on alert for possible further missile launches and other provocations by Pyongyang as North Korea is expected to sharply react to the US-South Korea joint drills.