Brent crude futures fell 0.1% to $101.10 a barrel, while U.S. West Texas Intermediate (WTI) crude rose 0.2% to $96.24 a barrel.
Brent prices have risen nearly 30% from the lows recorded in early August, as a deal between the United States and Iran to halt attacks was never reached, and fighting resumed late in the month.
Iran said it attacked 10 vessels near the Strait of Hormuz in retaliation for the United States sinking five Iranian oil tankers. Iran's Islamic Revolutionary Guard Corps warned it would intensify its response to any further attacks.
"The tit-for-tat attacks suggest oil flows from the Persian Gulf are likely to remain disrupted for the foreseeable future," said ANZ analyst Daniel Hynes.
Oil shipping volumes through the Strait of Hormuz remain significantly below pre-war levels.
Uncertainty over the actual volume of supply moving through the Strait of Hormuz, along with prolonged shipping disruptions, is keeping the physical oil market tense and preserving a geopolitical premium in oil prices, OCBC analyst Christopher Wong said.
According to LSEG, in the physical oil market, the price of the Dated Brent benchmark — which underpins the pricing of roughly two-thirds of the world's oil supply — has held above $100 a barrel since Sept. 3.
The U.S. Energy Information Administration (EIA) raised its oil price forecasts for this year and next, citing shrinking global inventories amid the loss of Middle East supply.
As previously reported, U.S. President Donald Trump said on July 22, 2026, that every time Iran attacked a vessel in the Strait of Hormuz, the United States would destroy a bridge or power plant in response.
Overnight into July 23, U.S. forces carried out their 12th consecutive night of strikes on Iran.
On July 23, 2026, oil prices rose to their highest level in more than six weeks as tensions escalated in the Red Sea and the United Statesu struck Iran again.
On July 30, oil prices fell despite fresh escalation in the Middle East.
On Aug. 10, 2026, oil prices rose amid uncertainty over whether the Strait of Hormuz would reopen.
On Aug. 17, 2026, tensions between the United States and Iran again shifted oil prices.
Oil prices dipped slightly on Aug. 21, despite the possibility of a second consecutive weekly gain, as the deadlocked U.S.-Iran conflict continued to disrupt supply from a key Middle Eastern oil-producing region.
On Aug. 27, oil prices continued to decline, responding to expectations that talks between Iran and Oman would help reopen the Strait of Hormuz.