By Kiyoshi Takenaka and Xiao Yu

TOKYO (Reuters) - Japan, China and South Korea agreed to urge North Korea to refrain from provocation and follow U.N. Security Council resolutions, after its latest missile launch towards Japan early on Wednesday.

Foreign ministers from the three Asian neighbours also sought to soothe their often-testy relations, and have reached an understanding on a trilateral summit meeting in Japan this year, a Japanese official said.

"We have confirmed that we will urge North Korea to exercise self-restraint regarding its provocative action, and to observe the U.N. Security Council's resolutions," Japanese Foreign Minister Fumio Kishida told a news conference after hosting the meeting with his Chinese and South Korean counterparts.

A North Korean submarine fired a ballistic missile on Wednesday that flew about 500 km (300 miles) towards Japan, a show of improving technological capability for the isolated country that has conducted a nuclear test and as series of missile launches this year in defiance of UN sanctions.

In the face of the North Korean threat, cooperation among Japan, China and South Korea was more important than ever, Kishida said after his meeting with China's Wang Yi and South Korea's Yun Byung-se.

Yun promised South Korea's support to realise a trilateral summit by year's end, as well as to cooperate economically and to achieve a successful summit of the Group of 20 big economies next month in China.

Wang said China opposed North Korea's nuclear and missile programmes and any "words or actions" that cause tension on the Korean peninsula, China's foreign ministry said in a statement.

China will continue to push for the peninsula's denuclearisation, seek a resolution through talks and uphold regional peace and stability, Wang added.

The three ministers share the understanding that Japan will host a trilateral summit this year, though dates have yet to be worked out, a Japanese Foreign Ministry official told reporters.


Relations between the three big Asian economies are often difficult with the legacy of Japan's wartime aggression affecting ties between it and China and South Korea, territorial disputes hurting links between Japan and China, and Japan and South Korea, and China suspicious of the others' U.S. ties.The meeting marked the first visit to Japan by a Chinese foreign minister since the Japanese government took over three of the tiny islands at the centre of a dispute with China, from private Japanese owners in September 2012.

"Trilateral cooperation is a very important part of East Asian cooperation," Wang told his counterparts at the beginning of the meeting.

"There are many problems existing between the three countries, but China, Japan and South Korea are the three biggest economy entities in Asia. It's our responsibility to promote economic development, lead regional cooperation and maintain regional peace and stability."

China's state-run Xinhua news agency said Wang's willingness to go to Tokyo showed "China's sufficient sincerity to cooperate with Japan and South Korea".

At the same time, it warned Japan and South Korea to "abandon the Cold War mentality and view the peaceful rise of China as vigour to regional development", while avoiding "being the tools for some countries outside the region to undermine regional stability."

Wednesday's meeting had earlier appeared in doubt after a flare-up in Sino-Japanese tension over their dispute over tiny islands in the East China Sea.

South Korea and Japan have a territorial dispute over small islands about half way between their mainlands.

Tensions have also been escalating between South Korea and China over a decision by Seoul and Washington to deploy an advanced anti-missile defence, which the allies say is meant to counter growing threats from North Korea.

(Reporting by Kiyoshi Takenaka and Xiao Yu; Additional reporting by Nobuhiro Kubo in Tokyo and Ben Blanchard and David Stanway in Beijing; Editing by Chang-Ran Kim, Robert Birsel)