SEOUL, South Korea - North Korea said Sunday it will resume disabling its key nuclear complex after the U.S. dropped the country from a terrorism blacklist - a breakthrough expected to help energize stalled talks aimed at ending the country's atomic ambitions.

The spat was the latest of many between Pyongyang and Washington that threatened to scuttle progress before eventually being settled since the international talks aimed at dismantling the communist country's nuclear program began five years ago.

This weekend's developments raised hopes that stalled international nuclear talks could quickly resume and help improve ties between Washington and Pyongyang - Cold War adversaries, still technically at war.

Experts still predict a long, bumpy road ahead before North Korea's nuclear program is ever dismantled.

The next stage "will be more complicated," said Cheong Seong-chang, a North Korea expert at the Sejong Institute, a private security think tank near Seoul.

Cheong said Pyongyang could ask for increasingly difficult concessions like the normalization of diplomatic ties with the U.S. and the withdrawal of American troops from South Korea before it completely dismantled its plutonium-processing facility at Yongbyon.

U.S. officials had insisted they would not take the North off its list of terror-sponsoring countries unless it accepted a through inspection of its nuclear program under an international agreement signed by North Korea, the U.S. and four other countries.

Washington's stance prompted the North to start reassembling the facilities at Yongbyon and bar international monitors from the site.

On Saturday, however, Washington announced it was taking the North off the list - which still includes Cuba, Iran, Sudan and Syria - saying Pyongyang had accepted all of its nuclear inspection demands.

Hours later, North Korea's Foreign Ministry announced it would restart disabling work and again allow U.S. and U.N. inspections at Yongbyon.

U.S. officials warned North Korea could again be placed on the blacklist if it ends up not allowing the inspections.

North Korea, for its part, said prospects for disarmament depend on whether the U.S. delisting actually takes effect and Pyongyang receives the remaining international aid promised under a 2007 deal reached with the U.S., South Korea, China, Russia and Japan.

Under that agreement, North Korea agreed to abandon its nuclear programs in return for diplomatic concessions and the equivalent of 1 million tons of oil aid. North Korea has complained that it completed eight out of 11 key disablement procedures, but has only received half of the promised aid.

"The terrorism delisting is just one step in getting the North to abandon its nuclear program," Kang Sung-yoon, a North Korea expert at Seoul's Dongguk University. "I think we'll face tiresome discussions on how to proceed with the verification."

Other developments have also sowed doubts over whether North Korea will follow through on its disarmament pledge - among them, the upcoming U.S. presidential elections that will see a new administration in office in January and questions over the health of leader Kim Jong Il. Though reported to have a suffered a stroke in August and North Korean media Saturday published photos of Kim inspecting a military unit.

The U.S. put North Korea on its terrorism list after communist agents allegedly planted a liquid bomb on a South Korea commercial jetliner in 1987, killing all 115 people after an explosion over the Andaman Sea near the Southeast Asian country of Myanmar. The North has denied involvement.