by Bay Fang

North Korea has provided the U.S. with a "significant number of documents" relating to their plutonium program, according to State Department spokesman Sean McCormack.

The move is seen as part of a process for the US to be able to verify the extent of the North's nuclear program.

"Our top three priorities are going to be verification, verification, verification," said McCormack. "So this is part of a process that is unfolding. We will see, perhaps, North Korea providing a declaration to China, who is the chair of the six-party talks. And these documents will play a role in that process."

The logs are like records for an audit, starting from the beginning of their plutonium processing campaign to now, according to a senior administration official.

They should reveal how much weapons-grade plutonium the North Koreans currently have, and enable the U.S. to check the veracity of any long-overdue declaration Pyongyang makes on its nuclear program.

The documents were reportedly handed over to the State Department's Korea expert, Sung Kim, who is at the end of a two-day visit to Pyongyang. Sung was in the North on his second visit in two weeks, in an intensifying effort by the Bush administration to break through an impasse over Pyongyang's nuclear program.

Under the terms of a landmark deal reached last year, North Korea agreed to provide a full declaration of its nuclear program by December 31, in exchange for economic incentives and removal from a US list of terror-sponsoring nations. The US says the declaration given by Pyongyang failed to come clean on an alleged illicit uranium program, and transfer of nuclear knowledge to other nations.

Last month, the U.S. released photographs of what it said was a nuclear reactor in Syria built with Pyongyang's help. The site was destroyed by an Israeli air-strike last September.

A new, tentative agreement between the two sides may have the North acknowledge US concerns about these omissions, but would not require the North to declare them openly. It would also set up a system for verification of the extent of Pyongyang's nuclear program.

Privately, the administration is celebrating the breakthrough. "These documents are hugely significant," said a senior administration official, who spoke on condition of anonymity. "They are the key to verification."

But some say that while the records are important, they will not be enough for Republicans in the Congress to approve lifting any sanctions on the North. "The bottom line is, this is useful information, but it may not be enough to satisfy the political requirement placed on the White House since the images were released about the Syria transfer," said Mike Green, who used to work on Asian affairs at the National Security Council. "It is not a full and complete declaration - it only covers the plutonium, not the issue of HEU [highly-enriched uranium] or proliferation, and Congress has said that it will agree to lift sanctions based on a full declaration."