North Korea's foreign ministry said late Wednesday that Cuban arms seized from a Pyongyang-flagged ship in Panama's waters were part of a legitimate deal and demanded the immediate release of the ship, state media reported.

"This cargo is nothing but ageing weapons which are to be sent back to Cuba after overhauling them according to a legitimate contract," the Korea Central News Agency quoted the foreign ministry as saying, adding: "The Panamanian authorities should take a step to let the apprehended crewmen and ship leave without delay."

North and South Korea failed Wednesday to reach agreement on reopening their jointly-run industrial estate as they wrangled over who was to blame for its shutdown.

A fourth round of talks about the complex again ended without agreement, but the two sides will meet again next Monday, said Seoul's chief delegate Kim Ki-Woong.

Cuba announced Tuesday that weapons found on a North Korean ship close to the Panama Canal were "obsolete" Soviet-era arms, which the communist island had sent to Pyongyang for repair.

The declaration came a day after Panama said it had found military equipment, which it believed to be missiles, after impounding the ship and conducting a drugs search.

A North Korean cargo ship stopped in Panama was carrying a radar that guides surface-to-air missiles to target, defense and security consultants IHS Jane's said Tuesday.

Panama announced Monday that it had intercepted the vessel Chong Chon Gang, which was en route from Cuba -- one of Pyongyang's only allies -- on suspicion it could be smuggling drugs.

South Korea on Tuesday blamed North Korea for a crippling cyber attack last month against several government and news media websites.

The accusation came a day before the two Koreas are to hold fresh talks on reopening their joint industrial zone, amid fading hopes of an early agreement following months of friction.

Panama's president said Monday that a North Korean ship captain tried to kill himself after the vessel was stopped en route from Cuba and found to have suspected missile material on board.

Outlining a dramatic sequence of events, President Ricardo Martinelli said the ship was targeted by drug enforcement officials as it approached the Panama Canal and was taken into port, but a search revealed cargo of far greater concern.

North and South Korea failed Monday to reach agreement on reopening a jointly-run industrial estate, dimming hopes of an early improvement in ties after months of friction.

A third round of talks about the complex, which followed two failed attempts this month, again ended without agreement, the South's unification ministry said.

China has lashed out at Japan over an official defense report by Tokyo, calling it untruthful and wrongly labeling Beijing a threat, state media reported on Friday.

The new Japanese defense white paper is the first since a long-simmering dispute with China and Taiwan over uninhabited islands in the East China Sea heated up last year.

North Korea has mobilized a variety of missiles in preparation for a massive military parade later this month to mark the 60th anniversary since the end of the Korean War, a report said Friday.

Satellite imagery has revealed more than 10,000 North Korean soldiers practicing for the parade at Mirim Airport near Pyongyang, Seoul-based Yonhap news agency said.

North Korea on Thursday retracted its proposal to hold talks with South Korea on restarting a family reunion program, after separate discussions on reopening a joint industrial estate faltered.

The North's sudden move came a day after the two Koreas agreed in principle to hold talks on reunions for hundreds of thousands of families separated since the 1950-53 war.