The ruling Pakistan People's Party on Saturday rebutted a claim by the country's disgraced nuclear hero that he transferred nuclear technology to other countries on the orders of its slain prime minister.

Abdul Qadeer Khan, whom many Pakistanis regard as a hero for building the Islamic world's first nuclear bomb, admitted in 2004 he ran a nuclear black-market selling secrets to Iran, Libya and North Korea.

He had offered a public apology but later retracted his remarks and in 2009 was freed from house arrest, although he was asked to keep a low profile.

On Saturday he said in an interview published in the mass-circulated Urdu language newspaper daily Jang and sister publication The News that he transferred nuclear technology on directives of slain prime minister Benazir Bhutto.

Khan did not name the countries, nor did he mention when Bhutto, the twice elected woman prime minister, issued the orders. Bhutto ruled from 1988 to 1990, and then from 1993 to 1996.

"At least 800 people are used to supervise the process. The then prime minister Mohtarma Benazir Bhutto summoned me and named the two countries which were to be assisted and issued clear directions in this regard," Khan said.

"I was not independent but was bound to abide by the orders of the prime minister, hence I did take this step in compliance with her order.

"The prime minister would have certainly known about the role and cooperation of the two countries, mentioned by her, in our national interest."

Bhutto's party spokesman Senator Farhatullah Babar described Khan's assertion as "a belated and desperate attempt to wash the guilt of proliferating nuclear weapons" by associating Bhutto's name.

It is an attempt "to lend a semblance of respectability to a crime that brought huge embarrassment and inflicted incalculable damage on Pakistan", Babar said in a statement.

"It is disgusting that almost a decade later Dr Khan should be seeking to restore his image by seeking to lay the blame at the door of the martyred Bhutto when she is no longer alive," he said.

Khan "now owes another public apology, after 2004, to the soul of Bhutto and her followers for levelling baseless and unfounded allegations against her", Babar added.

Bhutto, whose widower is Pakistani President Asif Ali Zardari, was assassinated on December 27, 2007 in a gun and suicide attack while leaving an election rally in Rawalpindi, the headquarters of Pakistan's army.

Khan launched his own Tehreek-e-Tahafuzz Pakistan or Save Pakistan Movement (SPM) party in July with a platform for fighting corruption, with the aim of promoting candidates in general elections due in 2013.