Washington:  The United States on Tuesday described North Korea's decision to temporarily stop disabling its nuclear facilities as a "step backward" that violated commitments under a six-nation disarmament deal.

The White House also made clear its position that Pyongyang must first fulfil its commitment to disable nuclear facilities before it could be struck off a list of state sponsors of terrorism.

"We understand that disablement activities have been halted temporarily and that North Korea has linked the resumption of these activities to the rescission of its designation as a state sponsor of terrorism," White House spokesman Tony Fratto said from Crawford, Texas, where President George W. Bush is on vacation.

"We've informed North Korea that we will take action to rescind its designation when it fulfils its commitment regarding verification," said Fratto.

US State Department spokesman Robert Wood voiced strong concern over North Korea's announcement that it would stop disabling its nuclear facilities and consider restoring the Yongbyon reactor that can make material for atomic bombs.

"It is clearly a step backward and we will be having discussions with our other partners in the six-party talks to see how things play out," said Wood, referring to China, Russia, Japan and South Korea which are involved in disarmament talks with Pyongyang along with the United States.

Verification mechanism

"It is a violation of their commitments to the six-party framework. It certainly is in violation of the principle of action for action," he added.

However, US Secretary of State Condoleezza Rice, on a visit to the Palestinian territories, sought to play down the North Korean announcement. "We actually are in discussions with the North Koreans and I think we'll just see where we come out in a few weeks," Rice told a news conference in the West Bank.

She said Washington had "made it very clear" in recent disarmament talks that "we are awaiting a verification mechanism that could assure the accuracy of North Korea's statement, or give us a way to verify the accuracy."

Being taken off the terrorism blacklist results in an end to many financial restrictions and would provide greater market access to Pyongyang.