The United States on Monday designated Iran's elite Revolutionary Guards as a terrorist organization, ramping up already far-reaching efforts to undermine the clerical government in Tehran - which swiftly retaliated by calling US troops terrorists.
It is the first time that Washington has branded part of a foreign government a terrorist group, meaning that anyone who deals with the Islamic Revolutionary Guard Corps could face prison in the United States.
President Donald Trump called the unit - which has some 125,000 troops and vast interests across the Iranian economy - Tehran's "primary means of directing and implementing its global terrorist campaign."
"This action will significantly expand the scope and scale of our maximum pressure on the Iranian regime," Trump said in a statement. Secretary of State Mike Pompeo, addressing reporters, said that all businesses and banks around the world "now have a clear duty" to cut off all dealings that involve the Revolutionary Guards.