Brent crude futures jumped 52 cents, or 0.54%, to $96.80 a barrel

Oil prices extended gains on Monday ⁠as tit-for-tat strikes between the U.S. and Iran on vessels sailing in the Strait of Hormuz and other areas heightened concerns of a prolonged supply disruption from the Middle ‌East.

Brent crude futures jumped 52 cents, or 0.54%, to $96.80 a barrel by 2354 GMT while U.S. West Texas Intermediate crude was ‌at $92.14 a barrel, up 66 cents, or 0.72%.

Brent gained 7.8% ‌last ⁠week while WTI added almost 10% after Iran and U.S. ⁠resumed attacks and caused a reduction in oil flows through the Hormuz strait where a fifth of the world’s oil supply used to transit.

On Saturday, Iran said it struck three additional U.S. naval vessels beyond the Strait of Hormuz, while the latter launched attacks on Iranian oil tankers.

The Saturday attacks represented a major escalation in the maritime conflict, maritime intelligence firm Marisks said.

Commercial tankers are ⁠now being deliberately used as instruments of reciprocal economic pressure, substantially weakening the previous distinction between military confrontation and commercial shipping, it added.

An average of 10 commodity ‌ships transited the Strait of Hormuz per day over the past 10 days, the lowest since May, data from analytics firm Kpler showed on Monday.

A restricted zone will be announced outside the Strait of Hormuz in coming days, Mohsen Rezaei, the secretary of Iran’s Supreme National Security Council, said on Sunday, according to state media.

Meanwhile, OPEC+ kept its oil output policy unchanged for ‌October at a meeting on Sunday, the producer group said in a statement, as it needs ​to agree new quotas before deciding its next output steps.