North Korea fired at least one "unidentified projectile" over the Sea of Japan on Thursday, Seoul's military said, with Tokyo reporting it as a possible launch of a ballistic missile.
The latest launch came a day after Pyongyang accused Japan of "transformation into a war state" as Tokyo beefs up its military stance in the Pacific.
"North Korea fires unidentified projectile toward East Sea," South Korea's Joint Chiefs of Staff said in a message to news organisations, referring to the body of water also known as the Sea of Japan.
"Something that may be a ballistic missile has been launched from North Korea," Japan's defence ministry posted on X.
A separate post shortly afterwards said "there is no longer any impact on the areas around Japan".
Tokyo's Defence Minister Shinjiro Koizumi said earlier this week the country's military needs to be boosted with a "sense of urgency and crisis", as a new government assessment warned of growing threats from China, Russia and North Korea.
In a statement carried by North Korean state media, Kim Yo Jong -- the powerful sister of leader Kim Jong Un -- said Pyongyang's "leadership will set up additional military options which are obviously due to Japan's transformation".
Pyongyang has repeatedly declared itself an "irreversible" nuclear state since leader Kim Jong Un's 2019 summit with US President Donald Trump collapsed over the scope of denuclearisation and sanctions relief.
The country has deepened economic and military ties with Russia, supplying troops and munitions for Moscow's war in Ukraine in exchange for financial support, food, energy and military technology, analysts say.
It has also repeatedly branded Seoul -- a security ally of Washington -- its "most hostile" enemy.
Japan's defence ministry declined to comment directly on Kim Yo Jong's Wednesday diatribe but said the country's defence capabilities "remain bare minimum" and "are not meant to threaten other countries".
"Ours isn't the defence meant to wage wars, but to prevent new wars, strictly kept to self-defence and within the scope of our (pacifist) Constitution and international laws," it said in a statement.
Tokyo raised its military expenditure by 9.7 percent to $62.2 billion in 2025 -- equivalent to 1.4 percent of GDP, its highest share since 1958.
China, a key ally of North Korea, has also recently expressed alarm at what it sees as "new militarism" by Japan.
South Korea's dovish President Lee Jae Myung has reversed the stance of his hawkish predecessor since taking power in Seoul in June 2025, offering nuclear-armed Pyongyang talks without preconditions.
The hermetic leadership of North Korea has yet to respond to his repeated offers.
The two Koreas remain technically at war because their 1950-53 conflict ended with an armistice rather than a peace treaty.
AFP
