WASHINGTON, 14 March 2004 — Information obtained from accused Pakistani nuclear scientist Abdul Qadeer Khan suggests North Korea began to pursue a highly enriched uranium program for nuclear weapons several years earlier than originally thought, US officials said yesterday.

The officials, interviewed by Reuters, cited this disclosure as evidence that Pakistan has been cooperative in sharing with Washington the secrets of Khan’s global network that sold nuclear technology to Iran, North Korea and Libya.

US allegations about an HEU program are central to six-party talks on North Korea’s nuclear program and US officials said they have used Khan’s information to buttress their case with their negotiating partners.

But officials also said that five weeks after Khan confessed his deeds, the United States still has not had direct access to the disgraced scientist, who is known as the father of Pakistan’s nuclear program.

Khan presumably could provide concrete answers to many key questions including whether he sold nuclear weapon designs to Iran, which claims its program is only peaceful.

Some US sources said the Bush administration was unhappy with Pakistan’s cooperation but a senior US official said these reports are “highly exaggerated.”

Asked if Islamabad’s cooperation was sufficient, the senior official replied: “I think we think it is an ongoing process.”

“We get regular briefings from the Pakistanis about what they are finding out and have been able to share this with other partners in the six-party talks” on the North’s nuclear program, he said.

But a second senior official said: “We don’t know what Khan has... We’ve been told that it’s coming.” “The Pakistanis are going to give us what they feel like giving us,” a third US source said.

Secretary of State Colin Powell is due to visit Pakistan as part of a South Asia trip next week and he is expected to discuss Khan and related proliferation issues with President Pervez Musharraf and other officials.

After saying he acted alone in nuclear trafficking, Khan was pardoned by Musharraf but remains in custody and apparently is being questioned by authorities. One of Khan’s recent revelations is that he began working with Pyongyang on an HEU program around 1991, not in the mid-1990s as officials had believed, two US officials said.

Khan supplied the North “with equipment for centrifuges for over a decade ending in 2001,” one senior official said. He declined to say if Khan provided documentary proof.

Another official said that just when Khan supplied actual centrifuges to Pyongyang remains unclear but there was “information exchange” and discussions about the “parameters of cooperation” on an HEU program as far back as 1991.

“It does suggest that the cooperation was somewhat earlier, that North Korea began HEU at an earlier date than might have been thought before,” he said.

Pyongyang admits to producing plutonium, the other major fuel for nuclear weapons, but has denied the HEU program.

One US official said the Khan information “has not changed our view that the year 2000 was the tipping point where Pyongyang went from an active R&D program to production of a full scale HEU program.”