North Korea urges Panama to release weapons ship
North Korea has urged Panama to release without delay its ship and crew, seized after weapons were found on board.
In its first comments on the case, the North Korean foreign ministry said the cargo of "ageing" Cuban arms was being sent for repairs and would be returned under a legitimate contract.
Panama earlier said the arms - hidden under a sugar cargo - were undeclared.
It also asked the UN to investigate whether there had been a breach of sanctions against North Korea.
The UN sanctions prohibit the supply of arms to Pyongyang in the dispute over its controversial nuclear programme.
"This cargo is nothing but ageing weapons which are to be sent back to Cuba after overhauling them according to a legitimate contract," the North's foreign ministry was quoted as saying by the state-run Central News Agency.
"The Panamanian authorities should take a step to let the apprehended crewmen and ship leave without delay," it added.
Cuba earlier admitted being behind the stash of weapons found on board the ship. It said they were obsolete Soviet-era arms from Cuba headed for repair in North Korea.
Meanwhile, the 35 crew members would be charged with crimes against Panama's internal security, local officials said.
The Chong Chon Gang ship was seized by Panama last week after "undeclared military cargo" was found.
Panamanian officials said the crew had failed to respond to communication attempts.
They said they had suspected the ship could be carrying illegal goods, initially thought to be drugs.
'Two more containers'
On Wednesday, Panama's Security Minister Jose Raul Mulino said officials had discovered "two more containers" with suspected arms, in addition to the two already confiscated.
He said Panama had asked the UN for advice on how to proceed in the case of the vessel being caught smuggling arms from Cuba through the canal.
Mr Mulino added that he expected Panama to hand over the ship and its contents to the UN.
The Cuban foreign ministry said in an earlier statement that the vessel was carrying 240 tonnes of "obsolete" defensive weapons - two anti-aircraft missile complexes, nine missiles in parts and spares, two MiG-21bis fighter planes and 15 MiG engines.
It said they were all made in the mid-20th Century and were to be repaired and returned to Cuba. The ship's main cargo was 10,000 tonnes of sugar.
Havana reaffirmed its commitment to "peace, disarmament, including nuclear disarmament, and respect for international law".
The vessel left Russia's far east on 12 April and travelled across the Pacific Ocean before entering the canal at the start of June, with Cuba as its stated destination.
It was stopped near Manzanillo on the Atlantic side of the canal last week, but Panama only released details of the find on Tuesday.
The vessel disappeared from satellite tracking systems after it left the Caribbean side of the canal, resurfacing on 11 July.
Experts say this may indicate that the crew switched off the system which automatically communicates details of their location.
Panamanian President Ricardo Martinelli posted on his Twitter account an image of a large green object inside a cargo container, saying it contained suspected "sophisticated missile equipment".
He added that even if the military cargo was found to be "obsolete", it was still "illicit" to carry it through Panamanian territory without prior notification.