SEOUL, April 15, 2026 (BSS/AFP) - North Korea accused Japan of a "grave provocation" on Wednesday after Tokyo laid out its opposition to Pyongyang's nuclear programme in an annual diplomatic paper.

The countries do not have formal diplomatic relations, and Pyongyang frequently criticises Tokyo over its colonial rule of the Korean peninsula, which ended with World War II.

The Japanese foreign ministry released its annual bluebook last week, detailing Tokyo's official diplomatic views and repeating its opposition to North Korea having nuclear weapons.

The position is "a grave provocation encroaching upon the sovereign rights, security interests and development rights of our sacred state", an unnamed North Korean foreign ministry official said in a statement carried by the official Korean Central News Agency.

North Korea's "measures for bolstering up its defence capabilities... belong to the right to self-defence", the statement said.

It described the bluebook as "woven with conventional gangster-like logic and absurdity".

North Korea has insisted that it will not give up its nuclear arsenal, describing its path as "irreversible" and vowing to strengthen its capabilities.

In its bluebook, Japan also expressed its unease that North Korea had sent troops and ammunition to Russia to aid its war against Ukraine.

Tokyo also downgraded its assessment of China for the first time in a decade, calling Beijing an "important neighbour" instead of "one of Japan's most important" partners.

It marked the latest deterioration in ties with Beijing since Japanese Prime Minister Sanae Takaichi indicated in November that Tokyo could intervene militarily in the event of an attack on Taiwan.

China views the self-ruled island as its territory and has not ruled out taking it by force.