The White House said Tuesday that it will remove North Korea from the list of state terrorism sponsors once Pyongyang comes through on its promise to disable its nuclear facilities, Reuters reported.

"We've informed North Korea that we will take action to rescind its designation when it fulfills its commitment regarding verification," White House spokesman Tony Fratto told Reuters.

Fratto's remarks came after North Korea said Tuesday it had stopped disabling its nuclear reactor and will consider restoring the plutonium-producing facility in anger over Washington's failure to remove it from the U.S. list of terror sponsors.

The North's statement marks the emergence of the biggest hurdle yet to the communist nation's denuclearization process and is expected to escalate tension in the nuclear talks involving China, Japan, the two Koreas, the U.S. and Russia.

Pyongyang's Foreign Ministry said it suspended the disablement work at the reactor and other facilities at its Yongbyon nuclear complex as of Aug. 14 because the U.S. did not keep its promise to delist Pyongyang as a terror sponsor under last year's deal.

The countries concerned were notified of the suspension, the ministry said.

"The U.S. postponed the process of delisting the (North) as a 'state sponsor of terrorism,"' the ministry said in a statement carried by the official Korean Central News Agency. "Now that the U.S. breached the agreed points, the (North) is compelled to take" countermeasures, it said.

The ministry also said the country will "consider soon a step to restore" the Yongbyon nuclear facilities, but did not elaborate.

The North's statement came shortly after Chinese President Hu Jintao left South Korea after summit talks with President Lee Myung-bak that included discussions on the nuclear issue.

South Korea's Foreign Ministry expressed regret over the North's announcement.

"We urge North Korea to resume disablement measures at an early date," the ministry said in a statement.

Removal from the terror list is one of the key concessions offered to the North in exchange for shutting down and disabling the reactor under a landmark six-nation deal reached last year.

In late June, the U.S. announced that it would delist the North as a terror sponsor after Pyongyang turned in a long-delayed account of its nuclear programs and blew up the reactor's cooling tower in a symbolic move to demonstrate to its denuclearization commitment.

The two sides have been negotiating how to verify the nuclear declaration, with Washington insisting it would remove the North from the terror list only after Pyongyang agrees to a verification plan.

That has angered Pyongyang. The North's state media have issued a series of commentaries blasting the U.S., and the Foreign Ministry last week threatened that the country would bolster its "war deterrent" — a euphemism for its nuclear programs — as it condemned U.S.-South Korea military exercises.

Analysts were divided over the North's intentions.

Yang Moo-jin, a professor at Seoul's University of North Korean Studies, called Tuesday's statement "very serious" and said that it could mean Pyongyang may have decided not to deal with the administration of U.S. President George W. Bush.

"I think this represents the biggest crisis to the denuclearization process since the Feb. 13 agreement," Yang said, referring to last year's disarmament-for-aid deal.

"The North's Kim Jong Il may have decided that he won't negotiate with the Bush administration any more" unless Washington takes Pyongyang off the terror list first, he said.

Bush is set to leave office in January next year. The U.S. will elect a new president in November.

But Cheong Seong-chang, a North Korea expert at the private Sejong Institute in South Korea, said the latest statement appeared to be aimed at pressuring Washington to lower its demands regarding verification and remove the North from the terror list.

North Korea began disabling the plutonium-producing facilities in November, but the process had been delayed because Pyongyang slowed the work in a row with Washington over how to declare the nuclear programs

South Korean and U.S. officials have said eight of the 11 disablement measures have been finished and that when the entire disablement is completed, it would take at least a year for the North to restart the facilities.

Whang Joo-ho, a nuclear expert at South Korea's Kyung Hee University, said it would take about three to six months for North Korea to restore its nuclear facilities at Yongbyon. He said it would take only one month to rebuild the kind of cooling tower the North destroyed in June.

The Associated Press contributed to this report.