Brent jumped 4.6% to 88.10 on fresh US-Iran tension. The move is the biggest one-day gain in months and came after the price sat at 84.23 the day before.

Why the price moved

The trigger is supply worry around the Strait of Hormuz, the narrow waterway that carries a big share of Middle East crude. When tensions rise, traders add a risk premium—the extra price buyers pay to cover possible disruption. No barrels have been cut yet, but the fear alone is enough to lift futures fast.

Who wins and who pays

• Upstream producers benefit directly: higher realised prices improve margins for ONGC and Oil India.
• Downstream players get squeezed: IOC, BPCL and HPCL face wider under-recoveries on fuel sales.
• High oil costs hit transport and manufacturing—airlines, tyre makers and paint companies all see input costs rise.

The one thing that reverses it

A quick diplomatic cooling between Washington and Tehran would remove the Hormuz premium almost overnight and send prices back toward the prior close.