Lawmakers from hardline Islamic groups and moderate opposition parties Friday walked out of the lower house of parliament to protest a startling admission from a Cabinet minister that a top Pakistani nuclear scientist sold centrifuges to Iran (search).

In a rare admission, Information Minister Sheikh Rashid Ahmed on Thursday said Abdul Qadeer Khan (search) sold the centrifuges to Tehran but insisted that the government was not aware of his activities.

"Dr. Abdul Qadeer gave some centrifuges to Iran," Ahmed told The Associated Press in a telephone interview. "He helped Iran in his personal capacity, and the Pakistan (search) government had nothing to do with it."

It was the first time a politician from either Iran or Pakistan publicly admitted the transfer of centrifuges, which could be used in making an atomic bomb.

On Friday, opposition lawmakers said Ahmed's remarks were highly irresponsible and could create problems for the nation. They called for a debate on the matter, but National Assembly Speaker Chaudhry Ameer Hussain rejected the request.

Dozens of angry lawmakers continued shouting their remarks over the speaker's objection, then walked out.

Qazi Hussain Ahmad, the leader of the Islamic political alliance, said Ahmed's remarks were "highly irresponsible."

"This is a very serious and sensitive matter and the house should hold a debate on it," he said.

Chaudhry Aitzaz Ahsan, a lawmaker from Pakistan People's Party, a moderate opposition group, also criticized the minister and praised Khan for helping Pakistan attain an atomic bomb. Khan is still considered a hero by many Pakistanis for single-handedly building a nuclear weapon to counter rival India.

Khan has been living under virtual house arrest since December 2003. The International Atomic Energy Agency has been investigating for more than two years evidence he sold nuclear technology to Iran, Libya, North Korea and others.

President Gen. Pervez Musharraf, who made Pakistan a key ally of Washington in its war on terror after the Sept. 11, 2001, attacks in America, pardoned Khan last year but restricted his movement.