"There is no need for the six-party [nuclear disarmament] talks any more," said the ministry's statement which was carried by the KCNA.
"We will never again take part in such talks and will not be bound by any agreement reached at the talks."
The North "will strengthen its nuclear deterrent for its defence by all means", the statement added.
"We will take steps to restore disabled nuclear facilities... and reprocess used fuel rods that came from experimental nuclear reactors."
Responding to Tuesday's statement, neighbouring Japan has called on North Korea to reconsider its actions.
|North Korea says the April 5 rocket launch placed a satellite in orbit [AFP]
Tthe UN Security Council meeting in New York on Monday issued a statement endorsed by all 15 members demanding an end to missile tests and saying it will tighten existing sanctions against Pyongyang should it conduct further launches.
The UN's first official response came eight days after North Korea launched a three-stage Taepodong-2 rocket over Japan.
The North insists the launch placed a satellite into orbit, and has defended what it says is its sovereign right to a space programme.
But the US military says no satellite has been detected and the rocket's upper stage and its payload crashed into the Pacific.
It says the North Korean launch was a cover for a test of a long range missile that could in theory hit the US west coast.
The non-binding UN statement was a weaker response to a full resolution which was sought by Japan and backed by the United States and its European allies, but opposed by China and Russia, the North's closest allies.
North Korea had been disabling its nuclear plants at Yongbyon, which produced weapons-grade plutonium, as part of a February 2007 six-nation aid for disarmament deal.
The talks, hosted by China, bring together envoys from the US, China, Russia, Japan as well as North and South Korea.
It had previously threatened to quit the talks, which began in 2003, should the Security Council criticise its April 5 rocket launch.