Oil extends gains amid U.S.-Iran diplomacy doubts

Oil prices surged on Thursday, building on gains from the previous day, as speculation diminished that diplomacy would quickly resolve the Iran conflict. By 04:01 ET, Brent crude futures were 1.1% higher at $104.19 per barrel, while U.S. West Texas Intermediate crude futures rose 0.9% to $92.99 per barrel. On Wednesday, Brent crude futures had risen more than 3%, while WTI crude climbed nearly 2%.

This rally followed Iranian President Masoud Pezeshkian's UN General Assembly address, where he asserted Iran would not submit to U.S. pressure yet remained open to talks. His remarks followed U.S. President Donald Trump's warning he could "annihilate" Iran if a deal to end the conflict was not reached. An Iranian official told Reuters Tehran was assessing Washington's response to an Iranian proposal to end hostilities, though key differences remained.

Discussions had considered reopening the Strait of Hormuz and lifting a U.S. naval blockade, as the waterway facilitates about one-fifth of global oil and liquefied natural gas shipments. Iranian security chief Mohsen Rezaei stated the strait would not reopen until Tehran's demands were met. These comments dampened hopes for improved Gulf supply, which had previously risen after Saudi Arabia restarted operations on its east-west pipeline to the Red Sea.

Iraq also increased exports. Concurrently, U.S. business activity data for the week ended September 18 boosted expectations for additional interest rate hikes by the end of the year. The Federal Reserve had already raised rates, citing the impact of the energy-price shock. Analysts at BCA Research noted that higher oil prices contribute to the Fed's hawkish stance.

Meanwhile, U.S. crude inventories increased by 3 million barrels to 426.4 million barrels, while gasoline stocks fell by 1.7 million barrels, and distillate supplies declined by 400,000 barrels. Reports suggested the White House was considering a 90-day ban on diesel exports, which sent U.S. ultra-low-sulfur diesel futures plummeting on Wednesday.