The United States is planning on designating the Iranian Revolutionary Guards Corps a foreign terrorist organization, three US officials told Reuters.
They said that Washington was likely to make the announcement on Monday.
It would mark the first time Washington has formally labeled another country’s military a terrorist group.
The Pentagon declined comment and referred queries to the State Department. The State Department and White House also declined to comment.
US Secretary of State Mike Pompeo has advocated for the change in US policy as part of the Trump administration’s tough posture toward Tehran.
The announcement would come ahead of the first anniversary of President Donald Trump’s decision to pull out of a 2015 nuclear deal with Tehran and to reimpose sanctions that had crippled Iran’s economy.
The administration’s decision to make the designation was first reported by the Wall Street Journal.
The United States has already blacklisted dozens of entities and people for affiliations with the IRGC, but the organization as a whole is not.
In 2007, the US Treasury designated the IRGC’s Quds Force, its unit in charge of operations abroad, “for its support of terrorism,” and has described it as Iran’s “primary arm for executing its policy of supporting terrorist and insurgent groups.”
Iran has warned of a “crushing” response should the United States go ahead with the designation.
Iran may put the US military on its terror list if Washington designates the IRGC as terrorists, a senior Iranian lawmaker said on Saturday.
“If the Revolutionary Guards are placed on America’s list of terrorist groups, we will put that country’s military on the terror blacklist next to ISIS,” Heshmatollah Falahatpisheh, head of parliament’s national security committee, said on Twitter.