North Korea threatened to launch a nuclear attack on the United States and turn Washington into “a sea of fire” after the United Nations slammed the outlaw nation with a tough new set of sanctions.

“Since the United States is about to ignite a nuclear war, we will be exercising our right to pre-emptive nuclear attack against the headquarters of the aggressor in order to protect our supreme interest,” Pyongyang’s Foreign Ministry blustered.

Army Gen. Kang Pyo Yong went further, telling a crowd of thousands that North Korea has long-range nuclear-armed missiles already targeting the United States.

“When we shell, [then] Washington, which is the stronghold of evils . . . will be engulfed in a sea of fire,” he said.

The United States said it was taking the threat seriously, but said Americans are in no danger.

“I can tell you that the United States is fully capable of defending against any North Korean ballistic-missile attack,” said White House spokesman Jay Carney.

Pyongyang’s outburst came after the UN Security Council unanimously approved sanctions to punish it for its latest nuclear test.

The sanctions were drafted by North Korea’s closest ally, China, indicating that Pyongyang is being deserted even by its friends.