By Stanley White and Chris Buckley
TOKYO/BEIJING (Reuters) - Japan is to send home 14 Chinese activists who were detained after some of them landed on an island claimed by both Tokyo and Beijing, but sour notes from Beijing and South Korea showed the latest flare-ups in territorial disputes were far from over.
Japan and China, Asia's two largest economies, have been at odds since the activists were detained on Wednesday after using a boat to land on the rocky, uninhabited isles known as the Senkaku in Japan and the Diaoyu in China.
Separately, Japanese Finance Minister Jun Azumi said he was postponing a trip to South Korea for a bilateral finance ministers' meeting scheduled for August 24 because of a trip made by South Korean President Lee Myung-bak to other disputed islands a week ago.
Japan will also review a bilateral currency swap agreement struck with South Korea last year, Azumi said.
The quarrels are among several dogging Japan's ties with neighbors China and South Korea nearly seven decades after the end of World War Two.
Beijing has demanded the immediate release of the Chinese activists after they reached the islands, which lie near potentially rich gas reserves.
Japan's Chief Cabinet Secretary Osamu Fujimura told reporters in Tokyo the activists would be deported.
"There is still some paperwork to go through, so I can't comment on exactly what time this will happen," he said, adding that arrangements for sending them back were nearly finished.
Despite that, the Chinese government indicated that resentment over the territorial dispute remained.
"China's stance on the Diaoyu Islands issue is clear and firm. Any unilateral measures that Japan takes regarding the Chinese nationals are illegal and lack efficacy," the Chinese Foreign Ministry's chief spokesman, Qin Gang, said in a statement on the ministry's website.
Qin also said the Chinese government was making preparations to "ensure that the Chinese individuals can return safely and smoothly and as soon as possible".
The comments were less stern than China's reaction in 2010, when tension flared after Japan seized a Chinese fishing trawler in the same waters after it collided with a Japanese patrol boat. Its captain was detained for more than two weeks.
Japan's relations with former colony South Korea also worsened after President Lee's August 10 visit to other islands believed to contain frozen natural gas deposits potentially worth billions of dollars.
Azumi said Lee's visit could not be overlooked.
Japan will propose taking the dispute to the International Court of Justice, Fujimura said, although that would be a largely symbolic move as South Korea's agreement would be necessary to open the case.
South Korean Foreign Ministry spokesman Cho Tai-young said Japan's proposal was not even worth consideration.
"This government will respond firmly to any provocations by Japan ... and Japan will be responsible for any consequences that arise," he said.
Earlier on Friday, Japan's Jiji News reported that police had handed the Chinese activists over to immigration authorities as a prelude to their deportation.
The renewed maritime tension with China has echoed China's recent tangles with Southeast Asian countries over rival territorial claims in the South China Sea.
China's expanding naval reach has fed worries that it could brandish its military might to get its way in the mosaic of sovereignty disputes in that sea.
(Additional reporting by Jack Kim in Seoul; Editing by Paul Tait and Robert Birsel)