Hook explained that the sanctions have definitely weakened the Iran Regime, denying the mullahs “billions of dollars of revenue through the loss of oil exports” and that eight months after Donald Trump announced he was leaving the Iran nuclear deal Iran is facing a “liquidity crisis” and the collapse of the rial.

Hook also stated that there would be no more oil sanctions waivers for Iran’s buyers once the current ones expire in May, showing that the US is going to get even tougher on Iran and choke off its sources of income.

Hook told a news conference in Abu Dhabi: “Iran is now increasingly feeling the economic isolation that our sanctions are imposing…We do want to deny the regime revenues. Eighty per cent of Iran’s revenues come from oil exports and this is (the) number one state sponsor of terrorism. We want to deny this regime the money it needs.”

He reiterated this during a panel discussion at the Atlantic Council’s 2019 Global Energy Forum, noting that he was pleased that countries that received the oil imports, like China, have cut their oil imports.

According to a report released Saturday by the Atlantic Council, Iran had reportedly sought to evade sanctions, including turning off their transponders on their oil tankers to stop their movements being tracked.

In the report, Hook said: “The Iranian regime, which is an outlaw regime, certainly tries to evade sanctions. We have, I think, organized the interagency in a way to make sanctions enforcement a big priority. And we have had a fair amount of success with it,”

The US sanctions on Iran, which came into place in August and November last year, came after the US withdrew from the 2015 Iran nuclear deal, which Trump said was biased in Tehran’s favour and failed to protect against the Regime’s malign behaviour, including its ballistic missile programme.

Hook emphasised that the US wants an improved deal with Iran, which is why they will put pressure on Iran to return to the negotiating table. Iran has so far refused to renegotiate its nuclear accord, but may soon be forced to choose between a new deal or the end of the Regime.