Japan on Tuesday criticised South Korea's plans to hold military exercises near disputed islands, warning Seoul that the move would stir up tension and further hurt relations.
"Increasing military tension would do no good in the goal of strengthening bilateral relations," Chief Cabinet Secretary Nobutaka Machimura, the government's spokesman, told a news conference.
He noted that while South Korea stationed maritime police on the disputed islands, it did not regularly post its military there.
"Under such circumstances, both sides should handle the issue cool-headedly, as we have repeatedly been saying," Machimura said.
The comments came a day after South Korean Defence Minister Lee Sang-Hee said Seoul will hold two major military exercises near disputed islands this year to prepare its armed forces for any provocation by Japan.
The dispute over the islands, called Dokdo in Korea and Takeshima in Japan, flared up again last week when Japan reaffirmed its claim to the islands controlled by South Korea.
Relations between South Korea and former colonial power Japan had been improving until the issue resurfaced. Prime Minister Han Seung-Soo on Sunday accused Japan of damaging ties and putting regional peace at risk.
South Korea cancelled plans for the two nations' foreign ministers to meet this week on the sidelines of a regional conference in Singapore.
South Korean President Lee Myung-Bak on taking office in February called for forward-looking relations with Japan and agreed to restart so-called "shuttle diplomacy," in which leaders of the two countries meet twice a year.
Asked whether the shuttle diplomacy was now off, Machimura said: "Making efforts to realise those events as scheduled is what diplomacy is all about."