Treasury Secretary Scott Bessent declared the start of an "economic D-Day" against Iran on Sunday. He described it as the single greatest financial offensive ever marshaled against an adversary.

US Targets Iran’s Economic Lifelines

Bessent stated that President Donald Trump had dismantled Iran’s military capabilities and destroyed nearly 100 percent of its military factories. He claimed the administration had also buried Iran's nuclear program.

"We are now entering the endgame," Bessent said in a post on X. He accused the Islamic Republic of dressing extortion as security guarantees and stated that era is over under President Trump.

The administration aims to sever every economic lifeline sustaining the regime. Bessent warned governments and entities supporting Tehran not to discount the cost of testing Washington.

Trump Escalated Economic Pressure

Last week, Trump announced a sweeping economic campaign against Iran. He called it the most crushing economic operation ever taken against any country.

The measures target oil smuggling, financial transfers, and shipping networks. Trump reiterated that Iran will never have a nuclear weapon.

Iran Warns Over Economic Pressure

Iran’s security chief Mohsen Rezaei warned Gulf countries against supporting the campaign. He said Tehran could consider them enemies and target their interests.

Rezaei warned that continued pressure could halt oil exports through the Strait of Hormuz. Iranian military officials threatened a crushing response to new sanctions.

These threats raised concerns about shipping disruptions and tighter global oil supplies. China, a major buyer of Iranian oil, could be particularly affected.

Rezaei previously stated Hormuz would reopen only after the US ended the war and blockade, released frozen assets, and agreed to a regional ceasefire.

Iran’s national security chief warned Gulf neighbors Saturday that joining Washington’s economic pressure campaign would designate them as enemies. Mohsen Rezaei stated Tehran would target the interests of participating countries.

The remarks aired on state broadcaster IRIB, citing Rezaei’s threat to escalate beyond targeting military bases if further US sanctions are imposed. This follows President Donald Trump’s campaign to isolate Iran’s economy, which he claims will have tremendous consequences for trading partners.

Rezaei Raises Stakes for Gulf Energy Trade

Rezaei, a former Revolutionary Guard commander and key adviser to Supreme Leader Ayatollah Mojtaba Khamenei, replaced Mohammad Bagher Zolghadr as secretary of the security council this month. He previously ran unsuccessfully for president.

Last week, Rezaei stated via X that the Strait of Hormuz would reopen only when the US ends the war and blockade, releases Iran’s frozen assets, and agrees to a region-wide ceasefire in Lebanon and Gaza.

In a post on X on Sunday, Rezaee warned that “not a single drop of oil will be exported” through the Strait of Hormuz or the Persian Gulf, “if the economic war continues,” reaffirming his earlier warning to countries participating in U.S. measures.

He added that Tehran would “regard any country’s participation in or support for America’s economic war against the Iranian people as an act of war.”

According to data collected by Marine Traffic, which tracks the movement of ships across the world, there were a handful of vessels traversing through the area at the time of writing this article.

Trump Pushes Economic Isolation Campaign

Trump has repeatedly called the Strait of Hormuz "new U.S. territory," a claim with no legal standing. The strait remains a critical bottleneck for roughly a fifth of global oil supply, keeping crude markets on edge.

Regional uncertainty has deepened with no signs of improvement. The UAE has suspended trade with Iran, while France and Saudi Arabia are set to discuss pipeline and rail alternatives to bypass the strait.

Trump had earlier said that the administration was preparing unprecedented financial sanctions aimed at Iran, a move that was also backed by U.S. Vice President JD Vance and Treasury Secretary Scott Bessent.

While Vance backed the measures, he also said that oil was moving through the Strait of Hormuz, a claim that was supported by Trump’s Energy Secretary Chris Wright.

Trump’s Environmental Protection Agency (EPA) also recently issued a waiver, allowing the release of winter blend gasoline earlier, touting the move as a relief to high prices at the pump.

Former General Says US May Have Lost Access to 15 Gulf Bases

Retired U.S. Army Gen. Barry R. McCaffrey said he believes the U.S. military has "probably permanently lost access to 15 Persian Gulf bases."

McCaffree added that the U.S. would have to “negotiate new access in western Saudi Arabia, Israel, southern Europe” and said that Tehran was “poised to control access [to] the Gulf States.”

Iran was earlier reportedly planning strikes against U.S. targets in Southern Europe, with Bulgaria’s Bezmer Air Base—where U.S. KC-135 refueling aircraft had been temporarily stationed—among potential targets. Two U.S. tankers left the base on Aug. 21, according to Bulgaria’s defense minister.

Analysts from Kpler also claimed that Iran had “partially lost” control over the Strait of Hormuz, saying that ships were transiting through the waterway via the Omani route.

Oil, Gas Prices

At the time of writing this article, the West Texas Intermediate (WTI) crude was trading at $85.64/bbl, while the Brent crude commanded a price of $93.05/bbl at press time. Meanwhile, the oil ETF United States Oil Fund (NYSE: USO) slipped 1.09% to $133.17 during overnight trading.

The national average price of gas remained above $4 on Sunday at $4.0986/gallon, while the national average price of diesel rose to $5.6074/gallon on Sunday. The average diesel price in California surged to $7.1423/gallon.