Oil plunges about 6% as Brent drops below $80 for the first time since 13 July

World oil prices plunged about 6% on Tuesday 4 August 2026. According to Anadolu Agency, Brent crude futures fell to around $79 a barrel as of 1550 GMT, down about 5.7% from the previous close of $83.77. It was the first time Brent has traded below $80 since 13 July. West Texas Intermediate declined about 5.9% to $75.60 a barrel from a previous close of $80.34.

The main driver was intensified diplomacy over reopening the Strait of Hormuz. US Treasury Secretary Scott Bessent told CNBC that negotiations were continuing and that a deal could be reached that day or the next. US Secretary of State Marco Rubio was more cautious the same day, saying: "There's been progress made in those talks, but not finality yet." Iranian Foreign Ministry spokesman Esmaeil Baghaei said Tehran is not holding direct negotiations with Washington and that talks under Omani mediation are focused on securing safe passage for commercial vessels. Qatar said a de-escalation plan is circulating but that no clear timetable for an agreement has been set.

A second factor was OPEC+ proceeding with a planned production increase of 188,000 barrels per day in September. The fall unwinds part of the geopolitical risk premium that pushed prices sharply higher in July. Crude is the single most important external variable for Iran's foreign currency earnings, and through that for the currency and gold markets and for refinery and petrochemical names on the Tehran bourse.