"Our military detected one suspected intermediate-range ballistic missile launched from the Pyongyang area towards the East Sea at around 14:55 (0555 GMT)," Seoul's Joint Chiefs of Staff said in a statement, referring to the body of water also known as the Sea of Japan.

The missile flew 1,000 kilometres (621 miles), the JCS added, saying that authorities in Seoul, Washington and Tokyo were analysing the specifications.

"We strongly condemn the latest missile launch by North Korea as it is a clear provocation that seriously threatens peace and stability on the Korean peninsula," it said.

Japan's coast guard also confirmed a suspected missile launch by North Korea, citing information from the country's defence ministry, and warning vessels to take care.

North Korea's last missile test was of a Hwasong-18 solid-fuel intercontinental ballistic missile (ICBM), which it fired into the East Sea on December 18.

The apparent test comes days after North Korea conducted a series of rare live-fire drills near its maritime border with the South, prompting counter-exercises and evacuation orders for some South Korean border islands.

Leader Kim Jong Un earlier this week branded Seoul his "principal enemy" and warned he would not hesitate to annihilate South Korea, as he toured major weapons factories.

"The historic time has come at last when we should define as a state most hostile toward the Democratic People's Republic of Korea the entity called the Republic of Korea (South Korea)," Kim was reported as saying by the official Korean Central News Agency (KCNA).

Analysts said at the time that the change in language was significant, signifying a shift in Pyongyang's approach to an "ultra-hawkish mode".

- Ties woeful -

Relations between the two Koreas are at one of their lowest points in decades, after Kim enshrined the country's permanent status as a nuclear power into the constitution and test-fired several advanced intercontinental ballistic missiles.

Last year, Pyongyang also successfully put a reconnaissance satellite into orbit, after receiving what South Korea claimed was Russian assistance, in exchange for arms shipments for Moscow's war in Ukraine.

Traditional allies Russia and North Korea have recently boosted ties anew, with Kim making a rare overseas trip to see President Vladimir Putin in Russia's far east in September.

Top Russian officials, including Moscow's defence and foreign ministers, also visited North Korea last year, with the flurry of trips both ways fanning concern among Kyiv's allies over the possibility of a potential arms deal.

KCNA said Sunday that Pyongyang's foreign minister would visit Russia this week.

Leif-Eric Easley, a professor at Ewha University, said the latest missile launch was "more than just a test", given its timing.

"It comes immediately after the Kim regime escalated warlike rhetoric toward South Korea and just before North Korea's foreign minister travels to Russia," he said.

"Pyongyang's show of force should be of concern beyond Seoul, as its military cooperation with Moscow adds to the violence in Ukraine, and because it may be more willing to challenge the US and its allies while global attention is fixed on the Middle East."

In 2023, Kim test-fired a string of advanced ICBMs including a purported solid-fuel version.

At Pyongyang's year-end policy meetings, Kim threatened a nuclear attack on South Korea and called for a build-up of his country's military arsenal ahead of armed conflict that he warned could "break out any time".

Pyongyang declared itself an "irreversible" nuclear power in 2022 and has repeatedly said it will never give up its nuclear weapons programme, which the regime views as essential for its survival.

The United Nations Security Council has adopted many resolutions calling on North Korea to halt its nuclear and ballistic missile programmes since Pyongyang first conducted a nuclear test in 2006.