An Iranian embassy official in Baghdad said Friday that under an agreement with the Iraqi government, the five will leave Iraq within a day or two.
The officials spoke on condition of anonymity because of the sensitivity of the issue.
Washington believes the Iranians, detained in northern Iraq in 2007, had assisted Shiite militants suspected of attacks on American-led forces in Iraq. Iran denies the claim.
U.S. officials say they handed the Iranians over to the Iraqi government at its request on Thursday, in line with a U.S.-Iraqi security agreement.