Iran has said it's ready for "war" or dialogue after President Trump said the U.S. was considering "very strong options" to intervene if Iran's security forces kill anti-government protesters in an ongoing crackdown. Vali Nasr, professor at Johns Hopkins School of Advanced International Studies, says the U.S. "can wage full-scale war on Iran — which President Trump does not seem to be eager to do — or it can hope to squeeze Iran economically in order to create political unrest in Iran."

This comes as at least 648 people have been killed since protests broke out in late December,  according to the Norway-based group Iran Human Rights, and over 10,000 people have been arrested. Iranian officials say the number of dead could be as high as 2,000.