Pakistan's probe into its secret nuclear programme has revealed limited approval of cooperation with Iran by former military ruler, General Zia-ul-Haq.

The interrogation of nuclear scientists has revealed that at least two Pakistani scientists acted inappropriately and exchanged information with Iran beyond the limit authorised to them by the government in late 1980s, The News reported on Saturday.

It said one of them could be booked for violating the Official Secrets Act.

The newspaper said General Zia had approved a request from the Iranian government in 1987 for an unpublicised cooperation in peaceful nuclear programme in non-military spheres.

"Just before his death in 1988, when I told Zia about Iran's growing interest in non-peaceful nuclear matters, he asked me to play around but not to yield anything substantial at any cost," The News quoted an unnamed retired nuclear scientist as saying.

The scientist, was, however, not very forthcoming about allegations about Zia's successor, General Aslam Beg, who was accused of trying hard to prevail upon the subsequent governments to help Iran develop nuclear technology.

The scientist, however, said he was aware of Beg's successor trying to do the same but did not name him.

"I don't know about the exact nature of transfer of technology that took place, but I knew that nothing moves in Pakistani nuclear spectrum without the knowledge of the chief of army staff," he said and questioned Beg's statement that the decision-making about nuclear programme was with former prime minister Benazir Bhutto and later with Nawaz Sharif.

The newspaper said investigating officials, however, do not discount Beg's influence and knowledge about the nuclear exchange that took place between some Pakistani and Iranian nuclear scientists in 1989-90.

An important voice in nuclear matters during that period was that of former president Ghulam Ishaq Khan. "If A Q Khan is the father of Pakistan's nuclear bomb, Ghulam Ishaq Khan was the grandfather," the newspaper quoted a senior official as saying.

Another nuclear scientist was quoted as saying: "From 1982 to 1993 Ishaq held the wallet for the nuclear programme,"

Ishaq Khan first arranged the finances for the nuclear programme as Zia's finance minister. He controlled that unique
position as the chairman, senate (1985-88) and as president (1988-93), The News said.

"Strategic decision making rests with the respective army chiefs, but Ishaq alone coordinated and controlled money matters as well as key strategic affairs. A Q Khan's most important patron in the government was Ishaq Khan," the official is quoted as saying.

Ishaq Khan, 83, resigned as president after losing majority in the parliament in 1993 and currently lives in his hometown in Peshawar where his relatives described him as "seriously ill."