On September 25, 2026, global oil prices showed a moderate decline after a sharp surge the previous day. At the close of trading, Brent crude futures fell 87 cents, or 0.82%, to $105.73 per barrel. The US benchmark West Texas Intermediate (WTI) showed a more pronounced correction: a drop of $1.56, or 1.65%, to $93.05 per barrel. Markets on that day were digesting signals of a possible ceasefire between the US and Iran, which exerted capping pressure on the "geopolitical premium" built into prices over the past weeks.
Weekly High and WTI Reversal
Equally notable was the price action in the preceding trading day. On Thursday, September 24, oil prices reached a weekly peak: by the close of the session Brent gained 3.4%, while WTI rose 2.7%. For Brent, this was the highest closing level since September 15. For WTI, by contrast, the rise was a landmark event after a prolonged slump: over the six previous trading sessions the US grade had lost 13%, and for the week it fell 6.42%. In the same period, Brent, conversely, posted a gain of 2.09%. This asymmetric character of the two key benchmarks' movement drew heightened attention from analysts and traders.
Record Spread and the Diesel Factor
By September 25, the gap between Brent and WTI prices reached $12.68 — the highest value since May of this year, when the spread exceeded $13. Usually the two benchmark grades move in sync, with US WTI traditionally trading at a discount to Brent. However, this time the divergence is anomalous. According to KCM Trade's chief analyst Tim Waterer, "the unusually large difference between WTI and Brent prices also reflects different regional risk profiles." To a large extent, this divergence is driven by market concerns over a possible US ban on diesel fuel exports. The administration of President Donald Trump, as previously reported, is considering a 90-day restriction on diesel exports to curb rising domestic fuel prices. Such a measure could lead to oversaturation of the US domestic market, which puts additional pressure specifically on WTI, while global Brent remains underpinned by Middle Eastern risks.
Diplomatic Track: New York and the Strait of Hormuz
The key geopolitical factor shaping oil market dynamics this week remains the talks between the US and Iran. According to available data, representatives of both sides in New York are discussing a phased path to resolving the conflict. The plan provides for Tehran to resume shipping in the Strait of Hormuz — through which about a fifth of the world's oil passes — and for Washington to lift the economic blockade on Iran as a reciprocal step. It was precisely these signals of possible de-escalation that became the main driver of the price decline on September 25: the market was pricing in the likelihood that the threat of closing key oil arteries would be removed.
Saudi Arabia Redirects Flows via the Red Sea
In parallel with the diplomatic track, industry sources, satellite imagery, and shipping data record operational moves by Riyadh. Saudi Arabia is increasing the volume of crude oil pumped through the East-West pipeline leading to the export terminal at the port of Yanbu on the Red Sea coast. However, according to available information, tanker loading at Yanbu had not yet resumed as of publication, meaning: the real increase in export supplies via the alternative route remains potential rather than actual. Nevertheless, the very fact of infrastructure preparation for redirecting flows lowers the risk premium on the Middle Eastern segment of the market.
Contradictory Data
Comparing various sources reveals a number of discrepancies worth noting. First, a number of publications (including the Kazakh outlet inform.kz) record Brent approaching the $95 mark amid Iranian tensions, whereas as of September 25, 2026 the price stands at $105.73. The difference is explained by the fact that those publications refer to an earlier stage of the escalation, but for a reader not tracking daily dynamics this may create an impression of inconsistency. Second, the nature of the diplomatic process is described differently: some sources speak of a "phased path to resolving the conflict," others of a "two-week ceasefire." Presumably these formulations reflect different stages of the same negotiation process; however, the exact duration and legal nature of the agreement reached (or planned) as of publication have not been officially confirmed by either side. Moreover, the divergence in the weekly dynamics of Brent (+2.09%) and WTI (−6.42%) of 8.5 percentage points has no precedent in modern market history and cannot be explained by the diesel factor alone, indicating the presence of additional, non-publicly disclosed pricing factors.
In the coming sessions, market attention will focus on two key events: the outcome of the New York talks between the US and Iran and a possible official announcement by Washington of a 90-day ban on diesel fuel exports. Either of these events could either narrow or further widen the anomalous spread between Brent and WTI, and also determine the direction of oil prices over the coming week.
