Iran offered to cut off aid and support for the Lebanese Shiite militia Hezbollah and the Palestinian group Hamas, and promised full transparency on its nuclear programme, in a secret letter to the United States soon after the 2003 invasion of Iraq, the BBC reported on Wednesday.
According to the BBC, the letter, which it obtained, was unsigned, but the US State Department understood that it came with the approval of the highest Iranian authorities.
The Islamic republic also offered to use its influence to support stabilisation in Iraq, and in return asked for a halt in hostile American behaviour, an abolition of all sanctions, and the pursuit and repatriation of members of the Mujahedeen Khalq (People's Mujahedeen MKO).