By Stanley White and Chris Buckley
TOKYO/BEIJING (Reuters) - Japan on Friday sent home the first group of Chinese activists detained after landing on an island claimed by both Tokyo and Beijing, but anger in China and South Korea shows the latest flare-up in territorial rows is 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.
Seven activists took off for Hong Kong from Okinawa, the Immigration Bureau said, and the rest of the 14-strong group were expected to head home by boat later on Friday.
Japanese television showed them making "V" signs as they were driven to the airport.
Japanese Finance Minister Jun Azumi postponed a trip to South Korea for a meeting with his counterpart 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, suggesting that Tokyo could consider cancelling the deal before it expires in October.
Japan occupied much of China during the war and colonised the Korean peninsula, the source of several feuds dogging relations with its neighbours nearly seven decades after the end of World War Two.
Beijing demanded the immediate release of the Chinese activists after they reached the islands, which lie near potentially rich gas reserves.
Tokyo's move to free them after questioning is seen as an attempt to cool things down given close economic ties that link Japan and China despite their troubled history and contemporary rivalry over resources and regional clout.
Despite that, the Chinese government indicated that resentment over the 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 Foreign Ministry's chief spokesman, Qin Gang, said in a statement.
Beijing resident Chen Quiyuan told Reuters he thought Japan's reaction showed China's tough stance was paying off.
"I think that the Japanese are exercising restraint for fear (of the consequences), and are trying not to blow up the issue."
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 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 and remarks seen as an insult to Emperor Akihito could not be overlooked. On Tuesday, Lee told a meeting of teachers that Akihito should apologise for "wartime and colonial excesses" if he wants to visit South Korea, saying a repeat of his 1990 expression of "deepest regrets" would not suffice.
Japan also confirmed its plan to take the territorial dispute to the International Court of Justice, although that would be a largely symbolic move as Seoul's agreement would be needed to open the case.
South Korean Foreign Ministry spokesman Cho Tai-young said Japan's proposal was not even worth consideration.
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.
(Additional reporting by Jack Kim in Seoul and Kiyoshi Takenaka in Tokyo; Editing by Nick Macfie)
