SEOUL (Reuters) – South Korea issued a strong protest against Japan’s territorial claim over disputed islands made in a national security strategy released on Friday while cautiously responding to Tokyo’s plans for an unprecedented military buildup.

South Korean President Yoon Suk-yeol who took office in May has tried to improve ties with Tokyo which have been marred by the territorial row over the islands and historic disputes stemming from Japan’s 1910-1945 occupation of Korea.

South Korea’s foreign ministry on Friday demanded an immediate removal of the territorial claims from Japan’s national strategy documents, saying in a statement that the move did nothing to help “building a future-oriented relationship” between the two countries.

The foreign ministry later said it summoned a senior diplomat from Japan’s embassy in Seoul to lodge the protest. The defence ministry separately said it summoned a Japanese defence official to protest the claim.

The islands known as Dokdo in Korea and Takeshima in Japan are controlled by Seoul with a small contingent of coast guards.

In a separate statement, the foreign ministry said it hoped the implementation of Japan’s new security policy will be transparent and contribute to regional peace and stability while continuing to uphold the spirit of is pacifist constitution.

Any exercise of attack capabilities against the Korean peninsula “must necessarily involve close consultations and agreement” with South Korea, it said, in an apparent reference to possible action to counter North Korea’s aggression.

President Yoon, who has made it a key national security priority to improve cooperation with Japan, told Reuters in an interview in November it was understandable for Japan to boost its defence spending given the growing threat from North Korea’s ballistic missile programme.