An initial review of documents submitted by North Korea about its plutonium nuclear programme appear to be complete, a US official said Tuesday, dpa reported.
North Korea has provided the United States with 18,822 pages of documents detailing its activities at the Yongbyon reactor and reprocessing site dating back to 1986 as part of a February 2007 disarmament agreement.
"They appear to be a complete set," said Sung Kim, the director of the US State Department's Office of Korean Affairs.
Kim returned from North Korea on Monday with seven boxes containing the documents, which he said will help the US verify North Korea's final declaration about all of its nuclear work.
Pyongyang missed a December deadline to submit the final declaration, slowing the implementation of last year's disarmament agreement produced by six-nation negotiations that included China Japan, Russia, the United States and the two Koreas.
North Korea pledged to end its nuclear programme in return for energy aid, diplomatic recognition and an end to sanctions.
"We believe these documents will provide an important first step in verifying the North Korea's declaration," Kim said.
"Obviously, the documents themselves alone is not enough," he added. "We would need to conduct a very full verification, including access to their facilities, sampling, interviews with personnel involved in the programmes."
Kim leads a US delegation that travels to the Stalinist state to oversee and verify that North Korea has complied with the agreement by shutting down and disabling its Yongbyon facility. Kim said eight of the 11 disablement steps have been completed and verified by his team.
North Korea has slowed down the disablement process to time it with the arrival of fuel shipments, Kim said.
"We would like to see it sped up a bit. I think at the current rate, we still have a few months to go," he said.
There could be remaining disputes over North Korea's declaration. Washington expects North Korea to disclose any role in helping Syria build the nuclear plant destroyed by Israeli warplanes in September, and to provide information about a suspected uranium enrichment programme.
North Korea denies a role in the Syrian reactor and maintains it only produced nuclear fuel through plutonium reprocessing and not by enriching uranium.