South Korea's president told the destitute North on Sunday to abandon its plans to develop weapons of mass destruction and return to talks with its capitalist neighbour.

Secretive North Korea has stoked regional tensions in the past weeks by readying a test-flight of its longest-range missile, which is designed to carry a nuclear weapon as far as Alaska but has never successfully flown, U.S. and South Korean officials have said.

North Korea has said it was preparing to launch a satellite and it had the right to do so as part of a peaceful space programme.

"Of all the countries in the world, South Korea cares most about the lives and happiness of the North Korean people. What protects North Korea are not nuclear weapons and missiles, but cooperation with the South and the international community," President Lee Myung-bak said.

"Denuclearisation is a short-cut for North Korea that allows it to grow into a member of the international community," Lee said in a speech to mark an uprising against the 1910-1945 Japanese colonial occupation of the Korean peninsula.

Analysts said the North was using brinkmanship to pressure the new U.S. government and its main allies in the region, South Korea and Japan, to reverse tough policies against the North. U.S. Secretary of State Hillary Clinton, on a trip to Asia in February, warned North Korea against any provocative moves.

In Beijing, Japanese Foreign Minister Hirofumi Nakasone urged North Korea to exercise "self-restraint", following a meeting with Chinese premier Wen Jiabao, spokesman Kasuo Kodama said.

"If North Korea test-fires such missiles, even if North Korea insists that it is not a missile but a satellite launched by a rocket, it is the view of the Japanese government that (that) runs counter to the existing UN Security Council resolution," Kodama told reporters, citing Nakasone.

"I would like to request North Korea to exercise self-restraint, not to escalate tension or anxiety in the region."

The Japanese and Chinese agreed to push forward with the six-party talks chaired by China, a framework that engages North and South Korea, China, the United States, Japan and Russia in negotiations to denuclearise the peninsula.

But Kodama said the Japanese impression was that the Chinese had not yet decided on a stance if the North Koreans claim to launch a satellite. The Chinese foreign ministry spokesman last week declined to comment on whether China considered the North Koreans as preparing for a missile or satellite launch.

Nakasone's brief visit to Beijing also addressed the disputed Diaoyu or Senkaku Islands in the East China Sea, but both sides agreed not to let that overshadow their broader relationship.

ASHES

North Korea has cut off dialogue with the South and threatened to reduce its rich neighbour to ashes in anger at Lee's policy of cutting off what once had been a free flow of unconditional aid and instead tying handouts to the North's disarmament.

Lee repeated an often-made call for the North to return to talks, while Pyongyang at the weekend labelled Lee a U.S. sycophant pushing the peninsula to the brink of war.

"The threat of missiles on the Korean peninsula comes from the United States and South Korea," Pyongyang's KCNA news agency said on Sunday.

"Their talking about the non-existent "missile threat" (from the North) ... is a tactic to justify their intention to invade the North and speed up building a missile defence system targeting us."

South Korean officials have said a launch would be met with sanctions and they do not see any difference between a missile or satellite launch because they use the same technology and the same rocket.

North Korea, which conducted a nuclear test in October 2006, does not have the technology to miniaturise a nuclear weapon to mount as a weapon, experts have said.

The reclusive state has also dragged down an international nuclear disarmament-for-aid deal by refusing to agree to a system to check claims it made about its nuclear programme. Pyongyang has complained aid has not been delivered as promised.