North Korea said on Saturday it would start a uranium enrichment programme and vowed to weaponise all of its plutonium in response to United Nations punishment for its nuclear test.
Pyongyang also threatened military action if the United States and its allies tried to isolate it.
The Security Council approved a resolution on Friday which banned all weapons exports from North Korea and most arms imports into the state. It authorised UN member states to inspect North Korean sea, air and land cargo, requiring them to seize and destroy goods shipped that violate the sanctions.
”We’ll take firm military action if the United States and its allies try to isolate us,” KCNA news agency quoted an unnamed Foreign Ministry spokesperson as saying in a statement.
He also said the North would start a programme to enrich uranium for a light-water reactor.
Experts said the North does not have the technology or the resources to build one of the costly reactors but may use the programme as cover to enrich uranium for weapons.
The spokesperson added that the North would ”weaponise all plutonium and we’ve reprocessed more than one-third of our spent nuclear fuel rods”.
North Korea responded to UN punishment for an April rocket launch, widely seen as a disguised long-range missile test, by saying it had restarted its plant the separates plutonium from spent fuel rods and threatening to test fire an intercontinental ballistic missile.
North Korea’s Soviet-era Yongbyon nuclear plant was being taken apart under a now-stalled disarmament-for-aid deal among Pyongyang and five regional powers. The spent fuel rods cooling at Yongbyon can produce up to one more bomb’s worth of fissile material, experts said.
The United States has long suspected North Korea, which has ample supplies of natural uranium, of having a programme to enrich uranium for weapons, which would give it a second path toward producing atomic weapons.
Impoverished North Korea for years has used its military threat to squeeze concessions out of regional powers willing to pay Pyongyang for taking steps that decrease regional risks.
Studies have shown that UN sanctions imposed on North Korea for missile testing and its only prior nuclear test in 2006 had almost no impact, while its meagre trade actually increased due to lax enforcement of those measures.
”The success of financial sanctions depends heavily on how far China and the United States are willing to go to pressure North Korea,” said Jeong Hyung-gon, a research fellow at the Korea Institute for International Economic Policy.
The isolated country’s $2-billion annual trade with neighbouring China, equal to about 10% of the North’s annual GDP, is its most important economic relationship. Beijing has wanted to avoid any measures that could cause the North’s economy to collapse and lead to chaos on its border.
Two senior diplomats negotiating the resolution told Reuters on condition of anonymity the Chinese had never really clarified whether they intended to implement the new sanctions resolution.
China’s UN ambassador, Zhang Yesui, said the resolution showed the ”firm opposition” of the international community to North Korea’s nuclear ambitions, but he urged countries to exercise caution when inspecting North Korean cargo.
A senior South Korean official said that North Korea may possibly respond to UN punishment with ”another nuclear test and maybe more missiles”.
”They will never, never give up their nuclear weapons,” said the official who asked not to be named due to the sensitive subject matter.
North Korea has raised tension in the region in the past months by test-firing missiles, restarting a plant to produce arms-grade plutonium and holding the May 25 nuclear test, which put it closer to having a working nuclear bomb. – Reuters