US designates Iran's elite Revolutionary Guard as terrorist organisation

US President Donald Trump on Monday designated Iran's elite Islamic Revolutionary Guard Corps a foreign terrorist organisation, marking the first time Washington has formally labeled another country's military a terrorist group.

Critics have warned that the move could open US military and intelligence officials to similar actions by unfriendly governments. The United States has already blacklisted dozens of entities and people for affiliations with the IRGC, but not the organisation as a whole.

"The IRGC is the Iranian government's primary means of directing and implementing its global terrorist campaign," Trump said in a statement.

The designation "makes crystal clear the risks of conducting business with, or providing support to, the IRGC," Trump said. "If you are doing business with the IRGC, you will be bankrolling terrorism." 

Secretary of State Mike Pompeo, a strident critic of Iran, has pushed for the change in U.S. policy as part of the Trump administration's tough posture toward Tehran.