According to South Korean military officials, North Korea fired a suspected ballistic missile off its east coast, its first known test since June.
It came after a US aircraft carrier arrived in South Korea to participate in joint exercises and ahead of Vice President Kamala Harris’s planned visit.
The launch, according to Seoul, was an “act of grave provocation.”
The United Nations forbids North Korea from conducting ballistic and nuclear weapons tests.
The South Korean military said it detected a short-range missile fired near Taechon, more than 100 kilometers (60 miles) north of Pyongyang, shortly before 07:00 local time (23:00 GMT). It claimed to have flown 600 kilometers at an altitude of 60 kilometers.
“Our military maintains a full readiness posture and is closely cooperating with the US while increasing surveillance and vigilance,” the statement said.
The launch was confirmed by Japan’s coast guard, who warned ships to “be vigilant.” Yasukazu Hamada, Tokyo’s defense minister, said the missile reached a maximum altitude of around 50 kilometers before crashing in waters off North Korea’s eastern coast, outside Japan’s exclusive economic zone.
“It’s North Korea’s way of defying the [US] alliance,” Soo Kim, a Rand Corporation analyst, told AFP.
On Friday, the nuclear-powered USS Ronald Reagan arrived in the southern port city of Busan to participate in joint drills off South Korea’s east coast. According to the South Korean navy, the exercises are being held for the “sake of peace and stability on the Korean peninsula.”
Ms. Harris will travel to South Korea in the coming days as part of a trip to the region that will also include a visit to the funeral of former Japanese Prime Minister Shinzo Abe.
Tensions on the Korean peninsula have risen in recent months, with Pyongyang launching a number of ballistic missiles.
Yoon Suk-yeol, South Korea’s new president, has promised a tougher stance against North Korea and closer ties with the US.
North Korea declared itself a nuclear weapons state earlier this month, with leader Kim Jong-un ruling out the possibility of denuclearisation talks. Pyongyang conducted six nuclear tests between 2006 and 2017, despite widespread sanctions.