Iran attempted to buy a nuclear bomb from Pakistan as early as 1987, a leading Middle East analyst has told Haaretz.

Documents obtained by Simon Henderson, a research fellow at the Washington Institute for Near East Policy and a former journalist, offer crucial evidence that Iran's nuclear program is not wholly for civilian purposes as it claims - but aimed at developing an atomic bomb.

Henderson told Haaretz he has acquired material written by the scientist Abdul Qadeer Khan - popularly known as the father of Pakistan's bomb program - while under house arrest between 2005 and 2009.

Khan was arrested by Pakistani authorities after it emerged he had for years been operating an 'atomic supermarket', touring the Middle East to peddle nuclear know-how to the highest bidder.

During his detention, Khan provided Pakistani security services with a wealth of detail on his sale of nuclear secrets to Iran and Libya in the late 1980s and 1990s, much of which is now in the hands of British and American intelligence.

But according to Henderson, Pakistan omitted to pass to its Western allies a sensitive report detailing visits to Pakistan in the late 80s by two Iranian officials, who Khan said offered $10 billion in exchange ready-made atomic bombs.

While Libya in 2003 publicly declared its nuclear program at and end, Western powers still suspect Iran of seeking a bomb, a charge it denies.

The report, obtained by Henderson, reveals that in 1987 or 1988 Admiral Ali Shamkhani, a former senior commander in Iran's Revolutionary Guard and minister of defense from 1997 until 2005, arrived in Pakistan with an entourage of officials.

Shamkhani offered to buy the nuclear devices on the spot and came prepared to take them home with him, Khan said.

The newly revealed material appears to confirm speculation that Khan, who despite his arrest remains a popular hero in his home country, did not act alone in selling Pakistani nuclear expertise to Iran and Libya, as Pakistan has claimed. Shamkhani's meetings suggest that Pakistani intelligence was aware of Khan's activities, as may have been the prime minister at the time, Benazir Bhutto.

Pakistan apparently refused Iran's offer - but Khan later traveled to the Middle East, where he auctioned his services as a private adviser. It was Khan who first provided Iran with designs for the centrifuges with which it continues to enrich uranium at its plant in Natanz.

Khan's other customer, Libya, eventually agreed to wind up its nuclear program and passed the CIA details of its transactions with the scientist. American intelligence was able to trace an elaborate smuggling operation in which the Pakistani had transferred bomb technology using front companies in Dubai.

In the Gulf emirate, Khan opened bank accounts under a variety of false names, including 'Khaidar Zaman', through which Iran paid him $5 million for his assistance.

As well as providing technical aid, Khan also gave the Iranians a list of Western suppliers of high-tech components vital to the enrichment process, who had helped Pakistan with its own bomb program.

As well as casting doubt on Iran's claims about the purpose of its nuclear research, Henderson's material could shed light on the thinking of Iran's Supreme Leader, Ayatollah Ali Khamenei.

Khamenei is believed initially to have opposed plans to acquire a bomb ? only to become convinced of its necessity in the early 1980s during a bloody war with Iraq, in which Saddam Hussein unleashed chemical weapons on Iranian troops.

Shamkhani, who now heads the Center for Strategic Research in Tehran and has been touted as a candidate for the presidency, is thought to be a close confidant of the Supreme Leader. His role at the center of Iran's attempts to gain a bomb may point to Khamenei's personal role in an Iranian bomb program.