North Korea on Saturday accused the United States of threatening war against the communist nation with its missile defense test, and vowed to strengthen its own self-defense to counter any US attack. The US on Friday carried out a key test of its missile defense system and succeeded in destroying a mock warhead over the Pacific Ocean. The test "was aimed at attacking us and intercepting our missiles," the North's Committee for the Peaceful Reunification of the Fatherland said in a statement, carried by the official Korean Central News Agency on Saturday. "It clearly shows that it is the US which is increasing tensions on the Korean Peninsula and threatening war against our country," said the statement, adding that such US pressure will only lead the North to strengthen its "self-defensive deterrent." Pyongyang often refers to its nuclear program as a self-defense deterrent. In July, the North heightened regional tensions by test-firing a barrage of missiles, including one believed to be capable of reaching the US The move drew strong international condemnation and prompted the UN Security Council to pass a sanctions resolution against the communist country. Concerns have also grown over a possible nuclear test by the North, following reports of suspicious activity in the communist nation. North Korea claims to have nuclear weapons, but has not conducted any known test to prove it has atomic bombs. "It is foolish for the US to think it can threaten us and make us surrender by wielding the stick of power," the statement said Saturday. "The US should be aware that it has nothing to gain from its reckless move to start war, and be fully responsible for the severe consequences from it," it added. North Korea has been boycotting six-nation negotiations on its nuclear program in protest against US financial restrictions imposed for alleged counterfeiting and money-laundering. Washington says the issue is separate from the disarmament talks and has demanded that Pyongyang return to the talks without conditions. The talks among the two Koreas, China, Japan, Russia and the US have been stalled since November, when negotiators failed to make progress on implementing a September agreement, in which the North pledged to give up its nuclear program in exchange for aid and security guarantees.