The Trump administration is imposing sanctions on Iran following its recent ballistic missile test.
The US Treasury Department announced the measures against 13 people and a dozen companies on Friday.
President Donald Trump tweeted earlier: “Iran is playing with fire – they don’t appreciate how ‘kind’ President Obama was to them. Not me!”
But Iran has said it will not yield to “useless” American threats from “an inexperienced person”.
John Smith, the US Treasury Department’s acting sanctions chief, said in a statement: “Iran’s continued support for terrorism and development of its ballistic missile programme poses a threat to the region, to our partners worldwide and to the United States.” Read more on bbc