Hormuz attacks and Iranian threats lift Brent toward a fourth monthly gain

Iran has stepped up attacks on shipping in the Strait of Hormuz, and its Supreme Leader has ordered unrestricted retaliation for any strike. Brent is heading for a fourth monthly gain while refiners report elevated margins.

What happened

Iran escalated attacks on commercial ships in the Strait of Hormuz in October. It hit at least 30 vessels and injured at least 16 seafarers [1]. On October 30, Iran's Revolutionary Guards attacked and halted three oil tankers, and Oman rescued 25 sailors from a burning merchant vessel, the RITI [2]. Iran also reported that four tankers struck mines. It disputed US claims that the main shipping lanes had been cleared, and UKMTO described explosives off Khasab, Oman, with the crew safe [3].

On October 31, Supreme Leader Mojtaba Khamenei ordered military chiefs to answer any US or Israeli attack with immediate, unrestricted force. The order covers all geography and targets, including civilian and economic assets, and calls for mobilising Hezbollah and Hamas [4]. The directive follows the four mine strikes and reports of planned US-Israeli strikes after the November 3 US elections [4]. Separately, the Houthis claimed six operations against Saudi airports and oil sites [3].

Oil flows have held up better than the attacks might suggest. Crude moving through the strait averaged about 11.1 million bpd in October, only about 2% below September. Shippers used a costly shuttle system, high freight rates encouraged risk-taking, and US military air cover was in place [1]. Weekly flows in late October nonetheless fell to 7.3 million bpd, more than 40% below the prewar baseline [1].

Brent traded at $116.56 and WTI at $103.35, and both were set for a fourth straight monthly gain. Reuters cited monthly gains of 11% and 14% respectively [5]. Another report put Brent's October rise at more than 13%, to above $117 per barrel [1].

FinUties' news monitor logged 23 reports on this story from 9 outlets in the last days, and 118 earlier related reports going back to December 8, 2025.

How we got here

The current escalation sits inside a war that began on February 28, 2026, when US and Israeli strikes hit Iran [2]. By mid-June, President Trump said negotiations on an Iran deal were nearing conclusion [6]. That did not hold. On July 8, NATO's Ankara summit closed with a show of unity despite overnight US strikes on Iran. Allies endorsed blocking an Iranian nuclear weapon and protecting Hormuz navigation [7]. By late July, US peace efforts on Ukraine had stalled amid a Trump administration shift of focus toward Iran [8].

By August 31, six months into the war, Iran's military had suffered major damage. Officials cited 80–90% attrition in its defence industry and missiles. Iran still disrupted transit through the strait, and Washington was pivoting toward an economic campaign against it [9]. On September 22, Trump told the UN General Assembly he expected an agreement with Iran immediately after the November 3 congressional elections, and he threatened severe consequences if none came [10].

The fuel market was already tight before October. On October 18, Trump signed an order pausing for 60 days sweeping Russia sanctions and tariffs that Congress had adopted in September. The order came two days before the law was due to take effect and followed a reported deal with Vladimir Putin on Russian diesel exports [11]. On October 19, Trump defended the waivers. He also criticised Ukrainian strikes on Russian diesel refineries for hurting global diesel markets [12].

What has changed in the last days is the tone around the election date. Trump has repeatedly suggested possible US strikes on Iran after the midterms, and media report US-Israel coordination [5]. Reports also say Washington may weigh renewed military action alongside outreach led by Vance via Qatar [3]. Iran's new directive signals that it will drop earlier military-only restraint [4].

Source: IMF Primary Commodity Prices (https://www.imf.org/en/Research/commodity-prices). Data as of Sep 2026. Markers: 1 = 31 Aug 2026, Iran Weakened but Defiant After 6 Months of War.

Why it matters for markets

Crude prices could stay sensitive to any shift in US protection of shipping or to the political situation after November 3. The strong October flows depended on US air cover and costly workarounds, and the late-October drop in weekly volumes raises questions about how long that can continue [1]. Houthi strikes on Saudi infrastructure and tanker attacks have outweighed resilient Persian Gulf exports in recent pricing [5]. The strait carries roughly one-fifth of global oil, so further disruption would raise supply concerns [2].

Refining could be a second channel. Chevron and ExxonMobil reported third-quarter profits far above Wall Street estimates, with US refineries running near full capacity as diesel prices surged globally [13]. The report linked higher diesel to attacks on refineries in Russia and the Middle East [13]. Shell, BP, TotalEnergies, Exxon and Chevron report sharply elevated refining margins, and tight fuel supplies could keep those margins high [14]. Global refining capacity is constrained by closures in Europe and North America, and the EU has shut a quarter of its refineries over two decades [14]. It is not yet known whether European policymakers will change course on refinery closures.

Natural gas could be a third channel. The Iran war and reduced Middle East LNG supply have pushed import costs to four-year highs. Europe and Asia have leaned toward renewables and coal for power while governments reprioritise energy security [15]. Chevron also said its international output slipped partly because of the Middle East conflict [13].

What to watch

• November 3 US elections. Reports tie possible US-Israeli strikes on Iran to the period after the vote [4][5]. Trump has also spoken of a possible deal with Iran right after the elections [10]. It is not yet known which path Washington will take.
• Iran's response. The new order covers civilian and economic targets and proxy groups [4]. It is not yet known whether Iran will carry out the threat.
• Hormuz flows and mine clearance. The gap between the 11.1 million bpd monthly average and the 7.3 million bpd late-October weekly figure is a key marker [1]. Iran disputes US claims that the main lanes are clear [3].
• Saudi infrastructure. Houthi claims of operations against Saudi airports and oil sites continue [3].
• Diesel and refinery supply. The 60-day Russia sanctions pause, which began around October 18, and Ukrainian strikes on Russian refineries both bear on diesel supply [11][12]. Refining margins remain a gauge of how tight fuel markets are [14].
• Geopolitical persistence. Geopolitical tensions are reported to persist into 2027 [14].

Sources

1. US Top News and Analysis: Tankers defy sharp escalation of Iranian attacks to keep crude oil flowing through Strait of Hormuz, 30 Oct 2026
2. World News: Latest International News & Updates | The Hindu: Oman rescues 25 from burning ship, Iran halts tankers, 31 Oct 2026
3. US Top News and Analysis: Iran claims four tankers struck mines in Hormuz as strike fears grow after U.S. midterms, 30 Oct 2026
4. Top Stories: Iranian military ordered to counter any attack swiftly and without restraint, 31 Oct 2026
5. Oilprice.com: Oil Prices Head for Fourth Monthly Gain as Middle East Tensions Escalate, 30 Oct 2026
6. US Top News and Analysis: Trump turns his attention to Ukraine ahead of Iran deal: 'I’m going to do whatever I can’, 16 Jun 2026
7. Oilprice.com: NATO Projects Unity as Leaders Rally Behind Ukraine, 09 Jul 2026
8. Oilprice.com: No Breakthrough as Top U.S. and Russian Diplomats Meet Over Ukraine, 24 Jul 2026
9. Oilprice.com: Iran Weakened but Defiant After 6 Months of War, 31 Aug 2026
10. tagesschau.de: US-Präsident Trump erwartet Abkommen mit Iran nach den Midterms, 22 Sep 2026
11. France 24: Rubio says Trump to 'analyze' global impact of Russia sanctions during pause, 18 Oct 2026
12. Al Jazeera: Trump defends Russian sanctions relief, lashes out at Zelenskyy, 19 Oct 2026
13. US Top News and Analysis: Chevron and Exxon hit all-time highs as refining profits soar in reaction to Iran and Ukraine wars, 30 Oct 2026
14. US Top News and Analysis: Trump called out Big Oil profits. Here’s how much their refining earnings have surged since, 31 Oct 2026
15. Oilprice.com: What’s Next for Global Natural Gas Demand?, 29 Oct 2026

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FinUties generates this briefing for transparency. Published after editorial review. It may summarize source data and does not provide investment recommendations. Data availability at one timestamp does not guarantee future continuity.

Provenance

• Study: event-desk-20261031-hormuz-attacks-and-iranian-threats-lift-brent-toward-a-fourt (3ea3f3d8-d4a1-4a85-9d4f-0098127ce718)
• Author: FinUties Research
• Approved by: FinUties Research at 2026-10-31T22:30:44.044655Z
• Kind: event brief (news sources, not a FinUties dataset study)
• Cited sources: 15 from 7 outlets, all licensed for public use

• Earlier related events cited from 2026-06-16

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