The United States struck Iran’s coastal defences and missile sites on Wednesday after reimposing a naval blockade of its ports, while Iran threatened to shut off more regional energy exports, saying it was engaged in an “existential war” with America.

After initially rising ​for a fourth straight session, Brent crude futures slipped 24 cents, or 0.28%, to $84.95 a barrel as of 0435 GMT, while ​US West Texas Intermediate futures fell 15 cents, or 0.19%, to $79.45 a barrel.

Brent had gained almost $1 earlier ⁠in the session, and both contracts remained close to one-month highs.

“Geopolitical risks remain firmly supportive for oil, but after a ​strong rally, traders are adopting a wait-and-watch approach,” Phillip Nova senior market analyst Priyanka Sachdeva said.

“The focus has shifted from the ​threat itself to whether there is any tangible disruption to oil flows and how both the US and Iran choose to respond in the coming days.”

Oil prices have gained this week as attacks deepened supply disruption in the Strait of Hormuz, which handled about a fifth of ​the world’s oil and liquefied natural gas trade before the war began.

Fewer vessels passed through the Strait of Hormuz on ​Wednesday, the first day after the US reimposed its naval blockade on Iran.

Seven crossed on Wednesday, down from 13 the previous day.

Hostilities ‌between Iran ⁠and the US reignited last week, fraying an already fragile truce reached in June after several months of fighting.

“While mediation efforts by neighbouring countries continue and the consensus view is that a full-scale war is unlikely, WTI could still rise to $85–$87 depending on how the conflict develops,” said Hiroyuki Kikukawa, chief strategist of Nissan Securities Investment.

Analysts say Iran has signalled it may ​use its Houthi allies in Yemen ​to shut the Bab El Mandeb gateway ⁠to the Red Sea, opening a new front against Washington and putting a second of the world’s most vital energy arteries at risk.

Reuters also reported on Wednesday that US officials said the strikes ​on Iran could pave the way for “more complex” operations against the country, adding to market jitters.

Goldman ​Sachs said Brent could ⁠exceed $110 in the fourth quarter if the Gulf export recovery continues to stall, but could fall into the $60s by year-end if tensions ease and production recovers faster than expected.

ING analysts cautioned in a note that the supply disruptions are flaring back up at ⁠a time ​when US commercial oil inventories are at the lowest levels since 2022, ​and the lowest levels for the season since 2018.

“The concern is that renewed oil supply disruptions come amid the large inventory drawdowns through the second quarter, ​leaving the market more vulnerable.”