The United States initiated a naval blockade of Iranian ports on April 13 at 14:00 GMT, aiming to halt the flow of Iranian oil and gas exports. This action has not achieved its immediate economic objective. Iran's oil revenues actually increased by 40% in the past month, according to trade intelligence firm Kpler. Tehran views the US blockade as "an illegal act" that "amounts to piracy," its armed forces stated.
The blockade's implementation swiftly escalated tensions in the critical Strait of Hormuz. Iran responded directly. It closed the waterway to all foreign shipping, a countermeasure to the US Navy's seizure of an Iranian-flagged tanker.
Washington had also redirected other vessels carrying cargo to or from Iran in open seas. Tehran's First Vice President Mohammad Reza Aref stated on April 19 that "the security of the Strait of Hormuz is not free." His comments, made on X, outlined a clear choice: "either a free oil market for all, or the risk of significant costs for everyone." This direct challenge to Washington's strategy quickly reshaped maritime trade routes. United States President Donald Trump, in a post on his Truth Social platform, claimed Iran was "collapsing financially." He asserted the country was "losing 500 Million Dollars a day." Trump also suggested military and police personnel were complaining about unpaid wages.
His post ended with a stark "SOS!!!" These claims, however, stood in contrast to recent revenue figures. The numbers on the shipping manifest tell the real story. Iran has managed to sustain, and even grow, its oil export income despite the US pressure.
Before the US naval blockade began, Iran was earning approximately $115 million daily from crude oil exports, totaling $3.45 billion in a month. In the period from March 15 to April 14, Iran's oil exports brought in at least $4.97 billion, even at a conservative estimate of $90 per barrel. This represents a 40% increase in oil revenues for Iran compared to the pre-war period.
Kpler, a trade intelligence firm, reported Iran exported 1.84 million barrels per day (bpd) of crude oil in March. Shipments continued at 1.71 million bpd so far in April, exceeding the 2025 average of 1.68 million bpd. Prices for Iranian light, heavy, and Forozan blend oil remained above $90 per barrel, frequently surpassing $100.
Frederic Schneider, a nonresident senior fellow at the Middle East Council on Global Affairs, told Al Jazeera on April 14 that the preceding six weeks had significantly boosted Iran's oil revenues. He predicted the US blockade would alter this trend. Schneider also noted on Friday that Iran appears to be "playing the longer game." They have anticipated this kind of conflict.
Iran possesses a buffer of approximately 127 million barrels of crude oil in floating tanks, essentially parked tankers, as estimated in February. This strategic reserve provides some flexibility. However, the naval blockade has introduced economic strain.
Several civilian ships have been captured in international waters. The effectiveness of the blockade remains uncertain. It is unclear how many ships manage to pass.
The considerable amount of floating Iranian oil complicates enforcement. Adam Ereli, a former US ambassador to Bahrain, explained to Al Jazeera's This is America programme that while the US blockade policy "makes sense," its intended effect might be undermined by domestic political considerations in the United States. He emphasized Iran's preparedness. "The Iranians have prepared for this, for this eventuality," Ereli said. "They have their own plans." They possess "alternative means of storing their oil or selling their oil."
Trade policy is foreign policy by other means, and this situation illustrates the complex interplay. Iran’s parliamentary speaker, Mohammad Bagher Ghalibaf, stated on social media that a full ceasefire could only be achieved if the US naval blockade is lifted. This links economic pressure directly to diplomatic outcomes.
It typically handles 20% of the world’s oil and liquefied natural gas (LNG) supplies from Gulf producers. Its near-shutdown following the US-Israel war on February 28 caused global oil and gas prices to soar. Iran has since maintained control, continuing its own energy exports through the waterway, with about 80% of its total oil exports passing through Hormuz via Kharg Island.
Iran, the third-largest oil producer in OPEC, also has substantial domestic refining capacity. FGE Energy, a consultancy, reports this capacity at 2.6 million bpd. Its oil and gas production facilities are concentrated in the southwestern provinces, particularly Khuzestan for oil and Bushehr for gas from the South Pars gasfield.
This localized concentration makes these areas strategically important. The US naval blockade has begun affecting Iran’s storage capacity. TankerTrackers, a maritime intelligence agency, reported that Iran brought an old Very Large Crude Carrier (VLCC) named NASHA (9079107) out of retirement.
This 30-year-old vessel, previously anchored empty for years, is now likely being used to store oil near Kharg Island. This is a vivid concrete detail. The move suggests Iran is preparing for potential storage shortages.
China has already voiced its concerns. It considers the blockade of Chinese trade with Iran unacceptable, according to Frederic Schneider. The continuing seizure of ships carrying Chinese cargo could escalate tensions further.
China's reaction remains a critical factor. The closure of Hormuz by Iran, in retaliation, impacts American allies globally, even if it does not directly affect the US itself as much. This elevates pressure on President Trump.
The situation highlights a patience mismatch: "If we can glean anything from the behaviour of the two sides, it is Iran that is signalling patience and Trump showing impatience," Schneider observed. Kenneth Katzman, former Iran analyst at the Congressional Research Service, indicated Iran currently has between 160 million and 170 million barrels of oil "afloat" on ships worldwide. These supplies, which transited Hormuz before the blockade, are awaiting delivery.
Based on information from an Iranian professor, Katzman told Al Jazeera that Tehran could sustain revenue flows from these supplies until August. This is a considerable timeframe. "Does President Trump have until August? Probably not," Katzman suggested.
Beyond oil exports, Iran is also generating revenue from a "toll booth" system imposed on the Strait of Hormuz in March. Iran’s deputy parliament speaker Hamidreza Haji-Babaei confirmed the central bank had received initial revenues from these tolls, as reported by the semiofficial Tasnim news agency. The exact amount remains undisclosed.
Iranian politician Alaeddin Boroujerdi told Iran International, a Farsi-language satellite TV channel, that some vessels have been charged as much as $2 million each to pass. Lloyd's List, a shipping news outlet, reported that at least two vessels paid fees in yuan, facilitated by a Chinese maritime services company acting as an intermediary. President Trump has also claimed "crazy" infighting within Tehran's leadership.
Iranian officials, however, insist on unity. Mohammad Reza Aref, Iran's first vice president, stated, "Our political diversity is our democracy, yet in times of peril, we are a 'Single Hand' under one flag." Foreign Minister Abbas Araghchi dismissed allegations of military-political discord, asserting, "The battlefield and diplomacy are fully coordinated fronts in the same war." President Masoud Pezeshkian reinforced this, saying, "In Iran, there are no radicals or moderates. We are all Iranians and revolutionaries." This unified front suggests a sustained resolve.
Iran has demonstrated considerable military resilience. It has faced weeks of US-Israeli strikes. Its asymmetric warfare strategy, involving guerrilla tactics, cyberattacks, and support for proxy groups, has been effective.
During the conflict, Iran targeted energy infrastructure in Israel and across the Gulf. It also threatened banking institutions and targeted US data centers of technology companies in the UAE and Bahrain. The reported placement of mines in the Strait of Hormuz further disrupted shipping, contributing to soaring global oil prices.
Such actions underscore Iran's capacity to inflict costs. Why It Matters: This ongoing standoff in the Strait of Hormuz directly affects global energy markets and, by extension, consumers worldwide. The volatility in oil and gas prices translates into higher costs at the pump and for heating, impacting household budgets and industrial operations.
The US blockade, intended to pressure Tehran, instead risks alienating key allies and trading partners like China, potentially fracturing international responses to regional stability. Follow the supply chain. Disruptions at this critical chokepoint ripple through global logistics, affecting not just energy but also the movement of a wide array of goods, raising shipping costs and extending delivery times for countless products.
Key Takeaways: - The US naval blockade has not reduced Iran's oil export revenues; they have increased by 40% in the past month. - Iran has retaliated by closing the Strait of Hormuz to foreign shipping and capturing vessels, impacting global trade. - Tehran possesses significant oil reserves in floating storage and is developing new capacity, indicating a long-term strategy. - The blockade exacerbates global energy price volatility and risks broader international tensions, particularly with China. Looking ahead, President Trump faces a legislative challenge by May 1. This is the deadline for maintaining a foreign offensive without congressional approval.
Kenneth Katzman suggested that if Trump seeks to conclude the situation on his terms, he might consider "kinetic escalation." China's stance will be critical. It has already stated its objections to the blockade impacting Chinese trade. The balance of patience between Washington and Tehran will determine the next phase of this confrontation, with global energy markets watching closely for any shifts in strategy or enforcement.
The potential for further disruptions to maritime trade routes remains. This directly impacts the cost of everyday goods globally.
Key Takeaways
— - The US naval blockade has not reduced Iran's oil export revenues; they have increased by 40% in the past month.
— - Iran has retaliated by closing the Strait of Hormuz to foreign shipping and capturing vessels, impacting global trade.
— - Tehran possesses significant oil reserves in floating storage and is developing new capacity, indicating a long-term strategy.
— - The blockade exacerbates global energy price volatility and risks broader international tensions, particularly with China.
Source: Al Jazeera
