Newly released correspondence from Osama bin Laden’s hideout in Pakistan contradicts U.S. assertions that al-Qaeda has a close relationship with Iran.

According to a U.S. analysis of letters found in the Abbottabad compound when U.S. Special Forces killed bin Laden a year ago, “the relationship is not one of alliance, but of indirect and unpleasant negotiations over the release of detained jihadis and their families, including members of bin Laden’s family.”

The report by the Combating Terrorism Center (CTC) at West Point, released Thursday, goes on to say that Iran’s detention of some prominent al-Qaeda members who fled Afghanistan after 9-11 “seems to have sparked a campaign of threats, taking hostages and indirect negotiations …that have been drawn out for years and may still be ongoing.”

Iran and the group that became al-Qaeda have had some sort of ties for more than two decades, but the nature of the relationship has been subject to considerable speculation and hype. The newly released documents suggest that the two are largely antagonistic and underline the view that the George W. Bush administration missed what could have been a major opportunity to work with Iran against the Sunni militant group responsible for the 9-11 attacks.