China, Japan and South Korea highlight unity amid North Korea moves

The leaders of China, Japan and South Korea met in Tokyo on Wednesday in a powerful gesture of solidarity against the backdrop of historic diplomatic moves by North Korea and a push for the isolated country to give up its nuclear weapons.

Last held in Seoul in 2015, the three-way summit has regularly brought together the East Asian neighbours, but this week's gathering comes amid an unusual period of calm for ties often beset by territorial and historical disputes.

Japanese Prime Minister Shinzo Abe will also hold separate meetings with South Korean President Moon Jae-in and Chinese Premier Li Keqiang, who is making a state visit, the first by a Chinese premier since 2010.

"For our three nations, building future-oriented cooperative relations is extremely important for the region as a whole," Abe said at the start of the trilateral meeting.

China has said regional cooperation will dominate the meeting, but Abe showed that North Korea will inevitably figure heavily following Moon's historic meeting with the North's Kim Jong Un last month, and ahead of an expected summit between U.S. President Donald Trump and Kim.

Praising Moon's recent leadership as well as Chinese moves to engage North Korea, which resulted in a sudden visit by Kim to China's Dalian on Tuesday, Abe said further efforts towards denuclearisation were essential.

"We'd like to build on these efforts as well as the actions of the United Nations to pursue complete, verifiable and irreversible denuclearisation," he said.

"We three nations need to stay in close touch with international society and demand that North Korea take concrete moves. This is essential," Abe said.

As Trump steps up trade pressure on China and Japan, the talks could provide an opportunity for improving regional unity, said Katsuhiko Nakamura, an official of a private think tank in the Japanese capital.

"It's meaningful to show that there's a united front like this in Asia, that there are different alliances in the world than those that have traditionally dominated," said Nakamura, a deputy executive director of the Asia Pacific Forum.

South Korea and Japan share concern about U.S. troops stationed in South Korea, whose numbers Trump has threatened to cut, while China and Japan are set to strengthen economic ties by signing a currency swap deal during the visit.

While tension lingers between South Korea and Japan over the issue of Korean women forced to serve in Japanese military brothels during World War Two, larger regional issues are pushing this to the background.

As the meeting's host, Abe has a chance to project himself in a key leadership role, drawing attention away from his domestic woes, ranging from suspected cronyism scandals and falling support rates to calls for his finance minister to quit.

This is especially true in the context of Japan's fears that it may be left out of North Korean negotiations, with Abe and Kim yet to set up a summit.

"Having the summit here allows Abe to put forth an impression of international leadership," said Nakamura.