Japan slammed a two-day military drill launched by South Korea as "unacceptable" on Sunday, after Seoul announced that its naval, air and army forces would take part in the maneuvers around the group of disputed islands called Takeshima in Japanese and Dokdo in Korean.

The Seoul-controlled islands are "obviously an inherent part of the territory of Japan," said Kenji Kanasugi from the Japanese Foreign Ministry.

The drills started only days after South Korea announced that it would stop sharing intelligence with Japan as tensions escalate.

'Comfort women,' smartphones

South Korea and Japan have been trading diplomatic blows since late last year, when a South Korean court ordered Japanese companies to compensate forced laborers who had worked for Japanese industry during the 35-year occupation of the Korean Peninsula.

The issue of forced labor and the "comfort women" used as sexual slaves by the Japanese troops still evokes strong emotions in South Korea. Japan claims that the issue of compensation has been settled by a 1965 bilateral treaty.

The escalation saw Japan tighten export restrictions on materials used by South Korean firms to make smartphone displays and chips. Some South Korean supermarkets removed Japanese products from their shelves, and both sides removed the other from their list of trusted trade partners.

Allies and opponents

South Korea has staged repeated drills around the disputed islands in previous decades, and the current exercises had been delayed due to the ongoing dispute, according to South Korea's Yonhap News Agency.

Japan lost control of the rocky islets in 1945, with its defeat in WWII also ending its 35-year colonial rule. A Japanese attack on Takeshima/Dokdo is considered highly unlikely.

The countries are both US allies and face a common threat from North Korea. Washington has been pushing for a closer alliance as a way to counter China's growing influence in Asia.

dj/rc (Reuters, AFP)

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