BEIJING — Japan has decided to deport Chinese activists who landed on a disputed isle at the heart of a territorial row, Kyodo news agency reported on Thursday, a move that could ease tension between Asia’s two biggest economies.

The dispute over the islands in the East China Sea has frayed relations between the two Asian neighbours, long bedevilled by the legacy of Japan’s wartime occupation of much of China and contemporary rivalry over resources and regional clout.

China had earlier on Thursday renewed its call that the detainees be released "immediately and unconditionally".

Wednesday’s landing, coinciding with the 67th anniversary of the end of the Second World War, parallels tensions between China and Southeast Asia over rival territorial claims in the South China Sea. China’s lengthening naval reach has fed worries that an aggressive Beijing could brandish its military might to get its way — and galvanised Chinese citizens’ demands for tough action.

Experts have said that both Beijing and Tokyo probably want to cool things down, given their close economic ties.

"But when issues touching on nationalism are involved, there are aspects politicians cannot control. Things will not be resolved automatically and careful responses are needed," said Akio Takahara, a Tokyo professor, before news that the activists would be deported.

Seven of the 14 activists arrested had waded ashore and planted a Chinese flag on the rocky, uninhabited isle on Wednesday, prompting Japan and China to trade protests over the incident.

China’s ruling Communist Party is preoccupied with a looming leadership change, which will probably both increase its focus on internal stability and deter it from seeming soft on Japan, a country many Chinese citizens still associate with wartime brutality.

"Just what kind of mentality has caused Japan to lose its self-restraint and repeatedly challenge China’s staunch determination to protect its territory and sovereignty?" said China’s Communist Party’s mouthpiece, the People’s Daily.

Small protests were held sporadically amid tight security near Japan’s embassy in Beijing. Meanwhile, China’s government faced a storm of online criticism from Chinese bloggers demanding a tougher stance to ensure the activists were quickly released.

Japanese Prime Minister Yoshihiko Noda, his popularity ratings tanking after about a year in office and possibly on his way out soon, also faces domestic pressure not to appear weak.

"The prime minister should visit the islands. If he doesn’t go at this point, it’s just plain lazy," the nationalist governor of Tokyo, Shintaro Ishihara, said.

His proposal for the Tokyo Metropolitan Government to buy the islands from their private owners ratcheted up tensions and pushed Mr Noda to try to have the central government make the purchase instead.

On Thursday, China’s commerce ministry urged Japan to handle the issue properly. "China hopes Japan can make concrete efforts to create a good environment for the sound development of bilateral economic and trade relationships and advance the development of the strategic and mutually beneficial relations," a spokesman said.

Japan’s relations with former colony South Korea have also nose-dived over a separate islands row. Adding to the anger of Japan’s neighbours, two Japanese ministers paid homage at a shrine for war dead on Wednesday.

A Japanese nationalist group is sponsoring a weekend trip by legislators and others to waters near the island, although the government has denied permission to land.

Reuters