The US is re-imposing sanctions lifted on Iran as part of the 2015 nuclear deal. Now any company doing business with Tehran could potentially face massive fines.
It follows President Trump’s decision to pull out of the Iranian nuclear deal, which was designed to curb the country’s nuclear programme.
The BBC’s Martin Patience reports from Beirut, Lebanon, where Iranians living there are already feeling the effects of the sanctions.
Iran sanctions: Face creams and carpets among products affected