Officials in US President Barack Obama's administration are drafting a letter to Iran from the president aimed at unfreezing relations and opening the way for direct talks, Britain's Guardian newspaper reported Thursday. The US State Department has been working on drafts of the letter since Obama was elected last November, the report said. It was a response to a letter of congratulations sent by Iranian President Mahmoud Ahmadinejad after Obama's poll victory. The letter gives assurances that Washington does not want to overthrow the Iranian administration, but instead seeks changes in its behavior, the paper said. It would be addressed to the Iranian people and sent directly to Supreme Leader Ayatollah Ali Khamenei, or released as an open letter. In Washington, a State Department official said the policy on Iran was under review and declined to comment on whether a letter was possibly being prepared to send to the Iranians. “No decision on any specific policy initiative has yet been decided by the State Department,” said the official, who spoke on condition of anonymity. Obama has said he was prepared to extend a hand of peace to Iran if it “unclenched its fist,” a break with the hardline policy of his predecessor George W. Bush, who branded Iran as part of an “axis of evil”. Iran said Wednesday it would welcome Obama's change of policy if it involved a withdrawal of US troops from abroad and an apology for past “crimes” against Tehran. The Guardian said the letter was being considered by Secretary of State Hillary Clinton as part of the review of US policy on Iran. A decision on sending it was not expected until the review was complete. The United States broke off diplomatic ties with Iran after students seized the US embassy in Tehran following the 1979 revolution.