North Korea threatened to conduct a second nuclear test and to test-launch ballistic missiles unless the United Nations apologises for condemning its recent rocket launch.
"Unless the UN Security Council offers an apology immediately, we will be forced to take additional self-defence measures to protect the highest interests of our republic," a foreign ministry spokesman said in a statement carried by the official Korean Central News Agency.
"They will include a nuclear test and ballistic missile tests," the spokesman said.
The Security Council in a statement condemned the North's April 5 launch and ordered tougher enforcement of existing sanctions, infuriating the communist state.
On April 14 it announced it was quitting six-nation nuclear disarmament talks and restarting the programme which produced weapons-grade plutonium. Last Saturday the North said reprocessing work has already begun.
The North, which tested an atomic weapon in October 2006, insisted its rocket launch was to put a peaceful satellite in orbit. Other countries saw it as a disguised long-range missile test.
The foreign ministry demanded that the 15-member council immediately apologise for "infringing" the country's sovereignty and retract "all its resolutions and decisions" against the North.
It also announced plans to build a light-water nuclear reactor.

Copyright 2009 AFP Asian Edition