US President Donald Trump has said he is imposing hard-hitting new sanctions on Iran, including on the office of the country’s Supreme Leader Ali Khamenei.
Mr Trump said the additional sanctions were in response to the shooting down of a US drone and “many other things”.
Ayatollah Khamenei, Iran’s highest authority, was singled out because he was “ultimately responsible for the hostile conduct of the regime”.
Iranian Foreign Minister Javad Zarif said the Americans “despise diplomacy”.
In a tweet sent after the announcement, Mr Zarif also accused the Trump administration of having a “thirst for war”.
Tensions between the two countries have been escalating in recent weeks.
However, US Treasury Secretary Steve Mnuchin said Mr Trump’s executive order – which would lock up “billions” of dollars in Iranian assets – was in the works before Tehran shot down an unmanned US drone in the Gulf last week.
The US Treasury department said eight senior Iranian commanders who “sit atop a bureaucracy that supervises the IRGC’s [the elite Islamic Revolution Guard Corps] malicious regional activities”, were being targeted.
It added that Mr Trump’s executive order would also “deny Iran’s leadership access to financial resources and authorises the targeting of persons appointed to certain official or other positions by the Supreme Leader or the Supreme Leader’s Office”, as well as foreign financial institutions which help them conduct transitions.
The US has alleged Ayatollah Khamenei has vast wealth which helps funds the IRCG. In a 2018 op-ed, US Secretary of State Mike Pompeo suggested his personal wealth was as much as $95bn which was “used as a slush fund for the IRGC”.
Sanctions will also be imposed on Mr Zarif later this week, according to Mr Mnuchin.
Back in May 2018, the White House reinstated all sanctions removed under a 2015 nuclear deall made with world powers which sought to prevent Iran creating its own nuclear weapon.
Relations between the two nations continued to sour, and in May – a year after Mr Trump abandoned the nuclear deal – the US stepped up pressure on Iran by ending exemptions from secondary sanctions for countries still buying Iranian oil.
This was followed by a series of attacks on tankers in the Gulf, which the White House said Iran was behind. Tehran has denied all allegations.
Iranian officials then announced the country was set to breach the limit on its stockpile of enriched uranium that was set under the 2015 deal on 27 June.
Days later, the drone was shot down over what the US says was international waters, but Iran says was its territory.