Former Iranian president Mahmoud Ahmadinejad has asked Barack Obama to return $2 billion of assets frozen in the US in a letter made public Monday.

Former Iranian president Mahmoud Ahmadinejad has asked Barack Obama to return $2 billion of assets frozen in the US in a letter made public Monday.

Ahmadinejad wrote that despite early promises by the US president to improve ties with Iran "the same hostile policies along with the same trend of enmity were pursued".

He specifically mentioned the $2 billion of Iranian foreign currency reserves seized from New York bank accounts earlier this year.

In April, the US Supreme Court confirmed an earlier ruling that the money should be used to compensate the families of victims of the 1983 bombing of a US Marines barracks in Lebanon and other incidents allegedly blamed on Iran.

Iran is appealing the decision at the International Court of Justice.

"I passionately advise you not to let the historical defamation and bitter incident be recorded under your name," Ahmadinejad wrote.