The Trump administration is considering declaring Iran's Islamic Revolutionary Guard as a terrorist organization, a proposal that would boost existing measures against the Islamic Republic's most powerful security entity.
As the Trump White House reviews its policy on Tehran, government officials say the change could come in the form of an executive order.
This comes as the White House toughened sanctions on Iran last week for its ballistic missile test as it ratchets up the pressure.
Critics worry the new designation could destabilize the Middle East and complicate the US fight against Islamic State in Iraq where Iran-backed fighters are battling the jihadist group.
Reuters also reported last week that officials were debating whether to declare the Muslim Brotherhood a terrorist organization, but that decision appears to have been indefinitely postponed.