Iran called the additional sanctions “outrageous and idiotic” and suggested the White House was suffering from a “mental illness.”

“That must mean that they are working if they are this upset about these sanctions. That’s an acknowledgement that they are working,” Mnuchin told CNBC’s Hadley Gamble in Manama, Bahrain on Wednesday.

After Trump withdrew from the 2015 nuclear deal in May of 2018, and reinstated sweeping sanctions on the country, tensions between the two countries spiked.

As well, Iran scaled back some of its commitments under the landmark accord last month, including on the amount of low enriched uranium it is allowed to stockpile, after Trump ended exemptions from U.S. sanctions for countries still buying Iranian crude.

The Trump administration believes that additional sanctions on Iran will force the country to renegotiate the Iran Nuclear Deal. John Bolton, U.S. National Security Advisor is saying Washington would be prepared to go further in order to get Iran to the table. “The president is willing to have conversations on the one hand — and doesn’t want war — but the president is also determined to enforce the U.S. and our allies’ interests in the region,” Mnuchin said.

Mnuchin answered the question of whether the U.S. is running out of room to maneuver when it comes to economic sanctions on Iran, by saying, “I don’t think so at all.”

He was also asked whether he was concerned about what U.S. Secretary of State Mike Pompeo said earlier this week — that more than 80% of Iran’s economy is currently under sanctions. “They are at about 80% now, we will ramp them up close to 100%,” Mnuchin said, before adding the White House would allow for “humanitarian activities” in an effort not to punish the people of Iran.

Eight countries who had waivers to import oil from Iran recently had them revoked. Washington has also applied financial restrictions to nearly 1,000 Iranian entities, including banks, individuals and vessels tied to the country’s shipping and energy sector. In May, the White House prohibited the purchase of Iranian iron, steel, aluminum and copper.

The U.S. is targeting Iranian oil exports to force Tehran to abandon support for militant groups in the Middle East and renegotiate the landmark nuclear accord.

Last week, according to U.S. officials, an Iranian surface-to-air missile shot down an American military surveillance drone over the Strait of Hormuz — the world’s busiest transit lane for seaborne oil shipments.

Iran claimed that the aircraft had violated its airspace. Trump declared soon after, that Iran made a “very big mistake” by shooting down the spy drone.

After Iran’s President Hassan Rouhani questioned the mental competence of the U.S. president, Trump threatened to attack Iran in retaliation for any strikes by Tehran “on anything American.”