A boatload of Taiwanese activists protected by the island's coastguard was Thursday heading for Japanese-held islands at the centre of a bitter international wrangle involving Tokyo, Beijing and Taipei.

The seven activists left port in Taiwan on a fishing vessel in the early hours and were expected to arrive in the area around the uninhabited islands about noon (0400 GMT), Taiwanese coastguard spokesman Shih Yi-che said.

A coastguard official in Japan said the vessel was "sailing towards the Senkakus".

The islands in the East China Sea, whose seabed is believed to harbour valuable mineral reserves, are known as Senkaku in Japanese and Diaoyu in Chinese. Both China and Taiwan claim them.

The group said it was on its way to plant a statue of a sea goddess believed by coastal communities in the region to have the power to protect seafarers, but it was not clear if the activists would attempt to land.

It also intended to "maintain sovereignty" against Japan's control, said Hsieh Mang-lin, the Taiwanese chairman of the Chinese Association for Protecting the Diaoyutais (Diaoyu Islands), in a short statement.

Japanese broadcaster NHK reported that Taipei had dispatched six patrol boats to "monitor" the ship, adding it was the same one that had entered waters off the islands in July.

Taiwan's coastguard denied it was an organised flotilla.

"Coastguard ships that patrol the area routinely will protect the boat," said spokesman Shih, who declined to give the number of official Taiwanese vessels in the area.

"The coastguard will protect our people's voluntary actions to defend the Diaoyu islands. Coastguard vessels will go wherever the fishing boat is... to defend our sovereignty and protect our fishing rights," a statement said.

In September coastguard vessels from Japan and Taiwan duelled with water cannon after dozens of Taiwanese boats were escorted by patrol ships into the islands' waters.

Earlier Japanese media reports had said there were Hong Kong activists on board the boat, but a spokesman for the southern Chinese territory's main Diaoyu protest group told AFP it was not involved.

Previous activist landings have resulted in the arrest and deportation of those setting foot on what Japan says has been its indisputable territory for more than a century.

The rocky island outposts have been the scene of a diplomatic tussle between Japan and China for months.

Japan's government nationalised three of them in September by taking them out of private Japanese ownership.

Since then, Beijing has repeatedly sent government ships into the waters. In December a Chinese government plane overflew them, leading Japan to scramble fighter jets.

Earlier this month both militaries had jets in the area and Japanese newspapers have reported that Tokyo is mulling allowing its pilots to fire warning shots.

While most commentators believe Asia's two largest economies will find some way to work around the problem, which has rattled relations for decades, some are warning that a mis-step could lead to armed confrontation.

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