The United States and the European Union say they are looking at imposing further sanctions on Iran, after its attack on Israel over the weekend.
US Treasury Secretary Janet Yellen said she expected to take action “in the coming days”, while EU foreign policy chief Josep Borrell said the bloc was working on it.
Israel has urged its allies to sanction Tehran’s missile programme.
United Nations sanctions over the programme expired in October.
Those sanctions had been linked to a wider deal to limit Iran’s nuclear programme.
However a number of countries including the US, EU and UK maintained sanctions and added new ones.
The Israeli military’s chief of staff, Lt Gen Herzi Halevi, said on Monday that the Iranian attack would not go unanswered.
Iran’s first-ever direct attack on Israel on Saturday saw a wave of more than 300 missiles and drones fired from Iran, Iraq, Syria and Yemen, with most being downed by Israel and its allies.
Tehran said the attack was retaliation for a presumed Israeli air strike on its consulate in Syria on 1 April, in which 13 people were killed.
So far, Israel appears to have countered with only a diplomatic offensive. Its foreign minister urged more than 30 countries to impose sanctions on Iran’s missile programme.
It has also called for the Islamic Revolutionary Guard Corps (IRGC) – a major military, political and economic force in Iran – to be designated a terrorist organisation, something the US has already done but the UK has not.
Speaking on Tuesday, US Treasury Secretary Ms Yellen said: “With respect to sanctions, I fully expect that we will take additional sanctions action against Iran in the coming days.
“We don’t preview our sanctions tools. But in discussions I’ve had, all options to disrupt terrorist financing of Iran continue to be on the table.”
She said Iran’s oil exports were “a possible area we could address”, adding: “Clearly, Iran is continuing to export some oil. There may be more that we could do.”
Ms Yellen added that the US was already using financial sanctions to isolate Iran and disrupt its ability to fund proxy groups and support Russia’s war in Ukraine – including by targeting more than 500 individuals and entities.
