TOKYO/BEIJING - Japan refused to apologize on Saturday for detaining a Chinese boat captain, showing no signs of softening in a dispute between the two economic powers after Japan gave ground and released him.
The fishing trawler captain, Zhan Qixiong, flew out of Japan to the coastal Chinese city of Fuzhou on Saturday.
The release followed the detention of four Japanese nationals on suspicion of violating Chinese law regarding the protection of military facilities, though Japanese Chief Cabinet Secretary Yoshito Sengoku has denied a link between the two incidents.
Japanese diplomats met the four on Saturday, Kyodo news agency reported. They have been under residential surveillance, meaning they were likely restricted at a hotel or lodging, it quoted an official at the Japanese Embassy in Beijing as saying.
China's Foreign Ministry said Beijing was angry at the detention of the captain, arrested by Japan over two weeks ago after his trawler collided with two Japanese patrol boats in waters near islands that both sides claim. It demanded an apology and compensation.
China said its claim to the islands -- which it calls the Diaoyu and Japan calls the Senkaku -- was "indisputable," but Japan did not agree.
China's statement had said that the two countries should solve their disputes through dialogue. Japanese Prime Minister Naoto Kan also said it was time for Asia's two biggest economies to put relations back on a steady footing.
"I believe it is necessary for Japan and China to handle matters calmly," he said in New York, where he attended the U.N. General Assembly.
The dispute has underscored the brittleness of ties long troubled by Chinese memories of Japanese wartime occupation and territorial disputes over parts of the East China Sea that could hold rich reserves of gas.
Sun Cheng, an expert on relations between the two countries at the China University of Political Science and Law in Beijing, said it would take time for relations to improve.
"China will want to keep up its case over the Diaoyu islands. Whether Japan actually apologies or gives compensation is not so much the point as making it clear that China won't compromise on sovereignty," he said.