Pakistan's army under President Pervez Musharraf supervised a shipment of uranium centrifuges to North Korea in 2000, the disgraced architect of Pakistan's atomic weapons program said Friday.

The claim is the most controversial leveled by Abdul Qadeer Khan, who in recent months has been agitating for an end to house arrest and backing off his 2004 confession that he was solely responsible for spreading Pakistan's nuclear arms technology to Iran, North Korea and Libya.

The retired scientist's comments could prove embarrassing for Pakistan, which has repeatedly denied the army or government knew about Khan's proliferation activities before it was reported uncovered in 2003.

His allegations also could become awkward for Washington in its support for Musharraf, who has been a key U.S. ally in the region but has seen his power and popularity at home slide over the past year from anger over his firings of judges and confrontations with Islamic extremists.

A spokesman for Musharraf rejected Khan's claims, calling them "all lies." But some Pakistani experts have long argued that Khan's network could not have operated without the knowledge of the country's pervasive intelligence agencies.

In a telephone interview with The Associated Press, Khan said a shipment of used P-1 centrifuges — which enrich uranium for nuclear warheads — was sent from Pakistan in a North Korean plane that was loaded under the supervision of Pakistani security officials.

Khan said that the army had "complete knowledge" of the shipment and that it must have been done with the consent of Musharraf, the army chief who seized power in a 1999 coup.

"It was a North Korean plane, and the army had complete knowledge about it and the equipment," Khan said. "It must have gone with his (Musharraf's) consent."

His allegations were first reported Friday by the Japanese news agency Kyodo.

Musharraf's spokesman, Rashid Qureshi, disputed Khan's charges. "I can say with full confidence that it is all lies and false statements," Qureshi said.

In a speech Friday, Musharraf himself made no mention of Khan's allegations while focusing on politics. He said he would not quit the presidency — as demanded by his opponents — and that he still has a valuable role to play. He called for Pakistanis to work together to fight Islamic extremism.

Spokesmen for the army and the Foreign Ministry declined to give immediate responses to Khan's charges.

Khan is regarded as a hero by many Pakistanis for his key role in the program that gave their country the Islamic world's first nuclear bomb in 1998, seen as a deterrent against the atomic arsenal held by neighboring India.

After his 2004 confession and a televised statement of contrition, Khan was pardoned by Musharraf but has effectively been kept under house arrest at his spacious villa in Islamabad.

Since a new civilian government took power after February elections sidelined Musharraf's supporters in parliament, Khan has increasingly spoken out in the media.

However, he had not previously implicated anyone or explicitly said that the army was aware of nuclear shipments. His comments Friday appear to stem from his growing frustration over the restrictions on his movements.

Khan and his wife retained an attorney earlier this week to petition the Islamabad High Court for an end to his detention. On Friday, the lawyer alleged that listening devices had been planted in the scientist's tightly guarded home.

Asked about his 2004 statements taking sole responsibility for nuclear proliferation, Khan said he had been persuaded that was in the national interest by friends, including Chaudhry Shujaat Hussain, a key figure in the ruling party at the time. Khan said he was promised complete freedom in return, but that "those promises were not honored."

Hussain could not be reached for comment Friday.

Khan's activities to spread nuclear weapons technology are alleged to have begun in the late 1980s, primarily to Iran.

In his 2006 autobiography, "In the Line of Fire," Musharraf said that in 1999, a year after becoming army chief, he became suspicious of Khan and questioned him over reports that North Korean nuclear experts had arrived at Khan's laboratories for secret briefings on centrifuges. Khan denied it, Musharraf wrote.

Musharraf recounted authorizing a raid on a chartered aircraft scheduled to go to North Korea to pick up a load of conventional missiles after receiving reports the plane would be carrying some "irregular" cargo on Khan's behalf. Khan's people were tipped off before the raid and never loaded the cargo, Musharraf wrote.

It was not clear if he was referring to the same shipment that Khan charges was loaded under army supervision.

Musharraf said his suspicions about Khan prompted him to remove the scientist in March 2001 from his position as head of the Khan Research Laboratories, Pakistan's main nuclear lab.

Pakistan's government insists it has tightened security for its nuclear arms since Khan's network was uncovered, saying a foolproof command and control system is in place to keep the weapons from falling into the wrong hands.

But Khan's accusation that the military establishment knew about his proliferation activities will bolster widespread skepticism that he could have kept his nuclear technology exports secret from Pakistan's security apparatus.

"No flight, no equipment could go outside without the clearance from the ISI and SPD and they used to be at there at the airport, not me," Khan said, referring to the powerful Inter-Services Intelligence agency and the Strategic Planning Division that manages Pakistan's nuclear arsenal.

Talat Masood, a political and military analyst, said it made sense that the proliferation effort was coordinated by more than one person.

"If the requirement of an aircraft was there, the requirement of dealing with another country was there, it's not just one man who could have done it," Masood said. "Whether they were doing it individually or collectively or as a state policy or informally — that needs to be determined."

Pakistan has refused to allow outsiders to question Khan, including experts from the United Nations' International Atomic Energy Agency, but says it has shared the findings of its own questioning of the scientist.

In his autobiography, Musharraf acknowledged that Pakistan bought conventional ballistic missiles from North Korea for cash in a government-to-government deal, but said it involved no transfer of nuclear technology.

Khan said he visited North Korea twice, in 1994 and 1999. On the latter trip, he said, he was sent by Musharraf to buy 200 shoulder-fired missiles when Pakistan and India were clashing in the disputed Kashmir region. He said he was accompanied on a special plane by an army general, Iftikhar Hussain Shah, and Pakistan paid cash for the weapons.

Khan was bitter in his criticism of Musharraf and confident of his own high standing among Pakistanis.

"People still respect me, and if anyone has any doubts and thinks himself more popular, he should go with me to Aabpara or Raja Bazar" — two markets in Islamabad and nearby Rawalpindi, Khan said.

Comparing the reception he would get to that which would be accorded Musharraf, Khan said: "You can cut my nose if his clothes remained untorn."