Treasury Secretary Scott Bessent is set to announce unprecedented U.S. sanctions against Iran on Monday, labeling them an “economic D-Day” and the “toughest in history” aimed at collapsing the Islamic Republic’s economy. President Donald Trump echoed these threats, promising “economic warfare and isolation on an unprecedented scale.”
However, Iran’s Islamic Revolutionary Guard Corps has dismissed these threats, asserting its capacity to circumvent sanctions and calling the U.S. moves an “implicit admission of the enemy’s humiliating defeat in the military arena.” Experts like Helima Croft from RBC Capital Markets question the effectiveness of further sanctions, noting Iran’s existing sanctions and its persistent disruptive capabilities in the region.
Watch Treasury Secretary Scott Bessent discuss the upcoming Iran sanctions.
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In a significant escalation of geopolitical tensions, Treasury Secretary Scott Bessent is poised to unveil a sweeping new package of U.S. sanctions against Iran on Monday, characterizing them as the most stringent and comprehensive “coordinated economic isolation in the history of the world.”
Bessent, in an opinion piece for The Financial Times on Sunday, dramatically declared the impending measures as an “economic D-Day — the single greatest financial offensive ever marshalled against an adversary.” The Treasury Secretary had previously vowed to CNBC that the U.S. intends to “collapse” the Islamic Republic through these unprecedented actions, explicitly stating they would be the “toughest sanctions in history.”
The Trump administration’s strategy demands global compliance, with Bessent asserting that U.S. allies and international partners must cease all business dealings with Iran. He warned that any nation failing to comply would face the “full might” of American economic power. “We are going to them and saying you are either with us or against us,” Bessent emphasized in his CNBC interview, adding, “It is time for our allies and the rest of the world to make a decision, and we are going to squash the economy of this murderous regime.”
This imminent announcement follows President Donald Trump’s own recent declaration that the U.S. would target Iran with the “most crushing economic operation ever taken against any country.” Trump further amplified this threat on Truth Social, stating, “this will be Economic Warfare and Isolation on an unprecedented scale.”

VIDEO: 19:08 — Watch CNBC’s full interview with Treasury Secretary Scott Bessent
Despite the formidable threats from Washington, Iran’s Islamic Revolutionary Guard Corps (IRGC) has defiantly dismissed the Trump administration’s warnings. An IRGC spokesperson conveyed via state media on Sunday that Iran possesses ample means “to counter the adverse effects of the enemy’s war” and can “easily establish economic relations with countries” elsewhere.
The spokesperson further characterized the U.S. president’s declaration of economic war as “an implicit admission of the enemy’s humiliating defeat in the military arena,” suggesting Tehran views the economic pressure as a concession of military impotence.
Helima Croft, head of global commodity strategy at RBC Capital Markets, weighed in on the efficacy of these new measures. She highlighted that Iran is already among the most heavily sanctioned nations globally, raising questions about whether additional economic pressure will genuinely alter Tehran’s behavior. Croft suggested in a CNBC interview that Iran might be banking on its ability to outlast an administration keen on a swift resolution.
Croft also cautioned that Iran retains “significant disruptive capabilities,” including the potential to target shipping in the Strait of Hormuz and critical infrastructure across the Middle East. “The question is how is this going to change with additional economic sanctions,” she mused, underscoring the complexities of forcing a policy shift through economic coercion alone.

VIDEO: 05:29 — RBC’s Helima Croft: Iran has significant disruptive capabilities; unclear how sanctions will help