The likely appointment of CIA Director Mike Pompeo as the new secretary of state following President Donald Trump's shock firing of Rex Tillerson could spell more bad news for Iran.
Pompeo, named as his pick for secretary of state by Trump on Tuesday shortly after he announced Tillerson's departure on Twitter, has taken a notoriously tough stance on Iran in the past in his erstwhile role as director of the CIA.
Not only has Pompeo likened Iran to the Islamic State (ISIS) militant group, calling the country a "thuggish police state" in a speech in October, he has also promised to constrain Iran's investment environment and "roll back" its 2015 nuclear deal.
Showing his disdain for the internationally-brokered agreement, Pompeo said in October that the U.S. intelligence community and Treasury Department could make it harder for Tehran to meddle in regional affairs by exposing Iranian businesses that have ties to the nation's elite security force.
The comment came shortly after Trump refused to certify the nuclear deal, marking the beginning of a campaign to toughen the terms of the agreement and rein in Iranian activities not addressed by the accord.
In November 2016, when Pompeo was appointed to lead the CIA, he warned that Tehran is "intent of destroying America" and called the nuclear deal "disastrous." He added that he was looking forward to "rolling back" the agreement.
Differences of opinion over how Iran should be treated are said to be the source of discord between Trump and Tillerson, whose firing followed a clash over the nuclear deal, the president said Tuesday.
"If you look at the Iran deal I think it's terrible and I guess he thought it was OK … We weren't really thinking the same," Trump said in a statement outside the White House. He said he and Tillerson got on "quite well" but had "different mindsets."
Iran has been increasingly marginalized during the Trump administration, which has sided with Saudi Arabia in the regional battle for influence in the Middle East.
International sanctions on Iran were lifted as part of the Barack Obama-era nuclear deal with Iran that was struck alongside the U.K., Russia, France, China and Germany. It allowed restrictions on Iran's economy and trading activities to be lifted as long as Tehran limited its nuclear energy program, which had long been feared as a cover for developing nuclear weapons.
Trump has been a vociferous critic of the deal since his election, saying that Iran had not stuck to it, although he has so far stopped short of tearing up or renegotiating the agreement.
In January, Trump decided to stick with the deal for now, but said its "terrible flaws" needed to be fixed. In particular, he wants so-called "sunset clauses" that would allow Iran to slowly resume its nuclear activities over the next decade to be removed.
Iran has said it would not accept any changes to the deal.