Brent ends October up 13.6% as Iran war risks unsettle markets
Brent’s December contract closes at US$117.64 a barrel as a tanker attack in the Strait of Hormuz deepens Middle East supply concerns.
- Brent crude's price increased by 13.6% in October, driven by market fears that the war involving Iran could intensify.
- Concerns over Middle East oil supplies were heightened by a tanker attack in the strategic Strait of Hormuz, a key export route.
- Attacks on Saudi Arabian oil facilities by Iran-backed Houthi militants also contributed to market uncertainty and the price surge.
Brent and US crude futures gained more than 2% on October 30, 2026, reaching their highest settlements since the end of April as traders worried that the Iran war could intensify after the US midterm elections. A tanker attack in the Strait of Hormuz added to concerns about Middle East oil supplies.
Brent’s October advance totalled 13.6%, while US West Texas Intermediate (WTI) crude gained 15.2% over the month.
The December Brent contract, which expired on October 30, finished at US$117.64 a barrel, up US$2.76 or 2.4%, after reaching US$118 during trading. January Brent, the more actively traded contract, advanced US$2.63 to US$113.43 a barrel.
WTI settled at US$104.12 a barrel on October 30, an increase of US$2.12, or 2.08%.
Hormuz tanker attack raises supply concerns
The United Kingdom Maritime Trade Operations (UKMTO), the British maritime security service, reported on October 30 that a tanker in the Strait of Hormuz had been struck by explosive devices attached from a small boat. Responsibility for the attack remained unclear. The strait is a key export route for Gulf crude and fuel supplies.
Maritime sources cited by Reuters described the Hormuz incident as the first known successful limpet-mine strike in the waterway since the US–Israeli war with Iran began in February. Limpet mines are explosives attached to a ship’s hull from a small boat.
Yemen’s Iran-backed Houthi militants claimed on October 29 that they had attacked several Saudi sites, including the large Ras Tanura refinery, the Rabigh refinery and a production facility at Abqaiq owned by state oil company Saudi Aramco.
A Saudi-led coalition reported intercepting a cruise missile launched by the Houthis towards western Saudi Arabia.
The US embassy in Riyadh announced on October 30 that non-emergency US government employees and their families had been ordered to leave Saudi Arabia, effective October 23. The embassy cited security risks from Houthi attacks on civilian airports and other critical infrastructure.
Qatari mediators return to Tehran for US–Iran talks
Qatari mediators returned to Tehran on October 30 as part of coordinated efforts to secure an agreement between the US and Iran, an official briefed on the negotiations told Reuters.
US President Donald Trump said on October 29 that Vice President JD Vance had contacted Iran to help the country obtain medical supplies. US media had reported that Vance wrote to Iran’s top security official in an effort to restart peace talks.
Iran’s semi-official Tasnim news agency reported that Tehran had received Vance’s letter but had not replied. Tasnim said Iran wanted the US to meet its conditions, adding that “any position that contradicts this framework is unacceptable.”
Saxo warns elections could increase oil price volatility
Denmark’s Saxo Bank warned in an October 29 briefing that oil prices could become more volatile over the following couple of weeks because of Israel’s recent elections and the US midterm elections on November 3.
Saxo Bank expects crude to trade at US$70–90 a barrel after the conflict ends, compared with the US$60–70 range before the war.
“Traders will remain focused on oil flows out of the Middle East and the likely escalation by US and allied forces,” said Dennis Kissler, senior vice president of trading at BOK Financial.
Saudi exports rise while Libya faces pipeline disruption
Saudi Arabia exported more crude in October than in September, according to two of three ship-tracking companies, despite Iranian attacks on Gulf shipping and Houthi claims of strikes on Saudi oil facilities.
Libya’s National Oil Corporation reported that an armed group closed a valve on the main Hamada crude pipeline on October 30, stopping flows of about 15,000 barrels a day. The pipeline connects the Hamada field with the Zawiya refinery.
The US oil rig count, which offers an indication of future production, rose by two.
US crude production increased in August while demand for crude oil and petroleum products fell, according to the US Energy Information Administration’s Petroleum Supply Monthly report released on October 30.
