Oil prices rose on Tuesday as prospects receded for a deal to end the Middle East war, with Iran saying it would adopt a more offensive stance and the United States ruling out extension of a ceasefire deal, heightening worries about energy supply.
Iran will shift to a "fully offensive" military posture as efforts have stalled towards a permanent end to the war, a senior Iranian official told Reuters on Monday, as Washington ruled out extending their temporary ceasefire pact.
Brent crude futures climbed 62 cents, or 0.7%, to $91.49 a barrel by 0408 GMT, after rising on Monday to their highest since July 30.
US West Texas Intermediate crude futures were up 75 cents at $85.25 a barrel, but off an earlier session gain of more than 1% to reach $85.37, their highest since July 31.
Outward progress on peace talks and resumption of oil tanker traffic through the strategic Strait of Hormuz has halted, threatening to extend the conflict the United States and Israel launched with attacks on Iran on February 28.
"Oil has jumped to start the week as US-Iran relations look increasingly shaky," said Tim Waterer, chief market analyst at KCM.
"A deal to reopen the Strait of Hormuz still does not appear to be in sight, and shipping numbers remain at a trickle."
A projectile struck a vessel transiting out of the Strait of Hormuz on Tuesday in the latest of the attacks that have kept crossings to the single digits, despite a slight rise from the weekend, tracking data showed.
"The lack of any kind of deal will have an impact on oil price expectations further out in 4Q and even in 2027," said DBS Bank's head of energy research Suvro Sarkar.
While the deal-related uncertainty lasts, he expected oil prices to range within $80 and $100 a barrel in the near term.
Iran has separately been negotiating with Oman an agreement on managing the Strait of Hormuz and says they are close to a deal.
US crude oil stockpiles were expected to have fallen last week alongside product inventories, a preliminary Reuters poll showed on Monday.
