Oil prices surged Monday as President Trump posted a stern warning to Iran, reigniting fears that the fragile cease‑fire could collapse. The U.S. administration’s threat came after weeks of stalled talks and a stalled reopening of the Strait of Hormuz, a key gateway for global oil shipments.

Brent crude leapt nearly 2 % to about $111 a barrel, while U.S. West Texas Intermediate climbed more than 2 % to roughly $108. The rally pushed oil‑related stocks higher, but the S&P 500 futures signaled a 0.6 % decline for the U.S. market once trading resumed.

Asian equity markets slipped, with mainland China, Japan and Taiwan falling, while South Korea’s KOSPI edged up. Gasoline prices stayed flat at a national average of $4.51 a gallon, a figure that has risen over 50 % since the conflict began, yet the daily cost to consumers remains unchanged this week.

The sharp rise in oil prices underscores the market’s sensitivity to geopolitical risk, as investors weigh the potential for supply disruptions against the backdrop of a tense U.S.–Iran dialogue. For energy companies, higher crude translates into tighter margins, while for exporters, a tighter Strait of Hormuz could squeeze global throughput.