TOKYO: Japan's prime minister on Thursday quoted comments by former British premier Margaret Thatcher about the Falklands War as he spoke about Tokyo's acrimonious islands dispute with China.

Shinzo Abe channeled the Iron Lady in a speech to parliament in which he talked about Japan's resolve to defend the islands claimed by Beijing in the East China Sea.

"Our national interests are immutable forever," Abe told lawmakers. "They aim at making the seas -- the foundation of our nation's existence -- completely open, free and peaceful."

Aggressors should never triumph, he said.

"Former Prime Minister Thatcher, recalling the Falklands War, said she tried to follow the principle that above all, international law -- the fundamental rule for the entire world -- must prevail against the use of force," Abe said.

The comments echo those by Thatcher in her autobiography in which she reflected about the 1982 conflict with Argentina over the ownership of the Falklands.

Thatcher sent a task force which recaptured the islands after a 74-day war which left 649 Argentines and 255 Britons dead.

While few observers see all-out war between Beijing and Tokyo over the Tokyo-controlled Senkakus, some have raised fears that a mistake or a miscalculation by a low-level commander could trigger a military incident.

In January Japan said a Chinese warship had locked its weapons-targeting radar onto a Japanese frigate and a helicopter in open waters near the islands.

Earlier Thursday Japan's coastguard said three Chinese surveillance ships were in the territorial waters of the island chain, which Beijing claims as the Diaoyus.

The dispute between Asia's two largest economies intensified in September when Tokyo nationalised three of the islands, in what it said was a mere administrative change of ownership.

In his speech, Abe reiterated his long-held position that the islands are an inviolable part of Japanese territory and that no dispute exists.

He noted that he had proposed the first rise in defence spending for 11 years in the context of repeated incursions by Chinese ships into waters around the islands, whose seabed is believed to harbour valuable mineral reserves.

"(But) the door to dialogue is always open," Abe said. "I will call on (China) to return to the start line -- a strategic partnership of mutual benefit that does not get derailed by single issues."

Abe, fresh from a summit with US President Barack Obama in Washington last week, vowed to strengthen the Japan-US alliance which he described as "precious".

Tokyo is also embroiled in island disputes with South Korea and Russia, while North Korea jangled regional nerves in February with its third nuclear test.

The premier said Tokyo wants to establish a forward-looking partnership with Seoul while trying to sign a peace treaty with Moscow by "seriously tackling" their territorial dispute.

The prime minister said he wanted to set up a Japanese version of the US National Security Council and called for a "national debate" on a possible change in the post-World War II constitution that imposed pacifism on Japan.

Abe has long harboured ambitions of rewriting a document which critics say hampers effective self-defence. Supporters say it is a bulwark against the Japanese militarism that blighted Asia in the last century.