"We... bitterly denounce the deployment of Stealth fighter bombers in South Korea by the United States as a... provocation of a war against the North and the worst malicious challenge to the Korean nation," the committee said in a statement.

It was Pyongyang's first official reaction to the deployment, which Washington described as "routine training".

"This proves that the US scheme of preemptive nuclear attack is systematically going over from violent words to operational plan and from the plan to the stage of military action," the committee said.

The deployment was also Washington's way of trying to spoil the atmosphere for an inter-Korean festival in Pyongyang on June 14-17 to celebrate the fifth anniversary of a watershed inter-Korean summit on June 15, 2000, it said.

"This is an unpardonable provocation tantamount to turning a gun mouth to the reunification fete of the Korean nation celebrating the fifth anniversary of the historical June 15 joint declaration," the statement said.

The United States and North Korea remain locked in a tense standoff over Pyongyang's nuclear weapons programme.

North Korea has boycotted China-hosted nuclear disarmament talks - which also include the United States, South Korea, Japan and Russia - since June last year.

In February the regime declared it had built nuclear weapons and vowed to increase its nuclear arsenals.