A flotilla carrying Japanese nationalists and lawmakers arrived Sunday at islands at the heart of a territorial row with China, with activists declaring their intention to land.

Around 150 people, including eight parliamentarians, got to the archipelago around dawn (2030 GMT Saturday) just days after Japan deported pro-China activists who had sailed there from Hong Kong.

The voyage came as Beijing told Tokyo it had to immediately cease actions "harming" its territorial sovereignty.

Local politician Eiji Kosaka told AFP some of the 20 vessels would seek to dock there. Another participant said activists and politicians wanted to walk onto one of the islands singing Japan's national anthem.

The Japanese government, which controls the islands, last week refused permission for any of the party to land.

An AFP journalist on board one of the boats said despite the early arrival, many participants had been awake to see the sun rise behind the islands.

Ahead of the voyage, Kenichi Kojima, a local politician from Kanagawa, near Tokyo, told AFP the trip was about who owned the archipelago, called Senkaku in Japan but claimed by China under the name Diaoyu.

"I want to show the international community that these islands are ours. It is Japan's future at stake," he said.

Parliamentarian Keiko Yamatani said most countries recognized Japan's sovereignty over the island chain, but added: "I think this kind of expedition will help raise awareness around the world."

Organizers said ahead of their departure that they would be holding a ceremony aboard boats moored "within touching distance" of the shore.

Beijing on Saturday rebuked Japan over the island visit.

"China has made solemn representations to Japan, demanding that it immediately cease actions harming China's territorial sovereignty," the foreign ministry said in a statement.

The dispute over the islands is one of the major stumbling blocks - along with issues related to Japan's military occupation of parts of China during World War II - to smooth relations between Asia's two giant economies.

Tensions spiked as Japan deported 14 pro-China activists who sailed to the islands from Hong Kong.

Some managed to land on an Uotsurijima, the largest island, becoming the first non-Japanese to set foot on any part of the archipelago since 2004.

"China reiterates that any unilateral action taken by Japan regarding" the islands "are illegal and invalid", Saturday's foreign ministry statement said, adding that any such actions will not undermine its claim over the territory.

Separately, a Japanese ruling party heavyweight said Saturday that his country should beef up its coast guard to defend the islands.

"Coast guard officials are doing their best, and so the government and the ruling parties will discuss how to strengthen our backup to them," Seiji Maehara, the policy chief of the Democratic Party of Japan, told reporters.

The renewed dispute came as tensions also rose between Japan and South Korea after President Lee Myung-Bak visited islets controlled by Seoul but claimed by Tokyo.

Emotions were running high around the August 15 anniversary of Japan's World War II surrender, with Beijing and Seoul angry about a visit to a Tokyo war shine on Wednesday by two Japanese cabinet members.

China's state-run Xinhua news agency reported Saturday that hundreds of people protested in the western city of Xian over Japan's detainment of the pro-China activists.

Demonstrators carried Chinese flags and banners, including one that read, "Salute the Chinese warriors who defend the Diaoyu Islands," Xinhua reported. It also said a small protest took place in front of the Japanese embassy in Beijing.

China's Global Times newspaper welcomed the release of the pro-China activists, but suggested that the dispute with Japan was far from over.

"As long as the Diaoyu Islands are still under Japanese control, there is no complete victory," it said in an editorial.

[image via Agence France-Presse]