"As our allies get the full picture, it doesn't help our credibility with them," he said.
Pritchard, now a Brookings Institution fellow, and others had initially raised questions about the Libya connection when it became public last month. No one in the administration has been willing to discuss the uranium sale publicly.
In testimony to Congress last month, CIA Director Porter J. Goss spoke extensively about North Korea's nuclear arsenal and capabilities. But he gave no indication the intelligence community believed that North Korea had supplied nuclear materials to Libya, that it was capable of producing uranium hexafluoride or that it was a member of the nuclear black market.
Two years ago, U.S. officials told allies that North Korea was trying to assemble an enrichment facility that would turn uranium hexafluoride into bomb-grade material.
But China and South Korea, in particular, have been skeptical of those assertions and are becoming increasingly wary of pressuring North Korea.
The National Security Council briefings in late January and early February, by senior NSC officials Michael J. Green and William Tobey, were intended to do just that by keeping the spotlight solely on North Korea.
Pakistan was mentioned only once in the briefing paper, and in a context that emphasized Pyongyang's guilt. "Pakistani press reports have said the uranium came from North Korea," according to the briefing paper, which was read to The Post.
After initial press reports about the briefing appeared last month, Pyongyang announced that it possessed nuclear weapons and would not return to the six-party talks.
Pritchard said North Korea's reaction was "absolutely linked" to the Green-Tobey trip.
The United States tried to persuade North Korea to return to the talks, but without success. The North Korean leadership responded with a list of conditions, including a demand that Rice apologize for calling it an "outpost of tyranny."
During the first stop on her Asian tour, Rice used noticeably softer language on North Korea, telling a Tokyo audience that the U.S. offer was open to negotiation, and that North Korean leader Kim Jong Il should grab the opportunity.
Staff writer Glenn Kessler contributed to this report from Seoul.