Oil Wrap: Iran Supply Fears Lift Crude; YPF Slips
Key Facts
- Crude benchmarks climbed to three-week highs as Iran said the Strait of Hormuz would remain closed and Washington ruled out extending a ceasefire.
- The USO fund ended at US$130.66 a gain of 0.28% on Tuesday, tracking front-month WTI futures rather than the spot barrel.
- Petrobras slipped to US$18.18 down 0.38%, even as investors weighed new pre-salt licensing interest and the Morpho well confirmation.
- YPF fell 3.83% to US$50.68 handing back part of Monday’s 5.29% surge tied to Argentina’s Vaca Muerta shale outlook.
- Ecopetrol was nearly flat at US$17.68 up 0.06%, a muted response to the session’s geopolitical supply alarm.
- Brazil’s pre-salt auction drew 19 qualified bidders including Repsol and Ecopetrol, underscoring foreign appetite for deepwater reserves.
Today’s Focus
Oil rode a fresh Iran supply scare higher on Tuesday, with both WTI and Brent settling at their strongest levels since late July. The trigger was Tehran’s vow to adopt a more offensive posture and keep the Strait of Hormuz closed, while Washington said the US-Iran ceasefire would not be extended.
The WTI-tracking USO fund rose 0.28% to US$130.66 in New York trading. Petrobras lost 0.38% to US$18.18 despite bullish Brazilian exploration news, while YPF gave back 3.83% to US$50.68 after Monday’s sharp Vaca Muerta-driven rally.
For Latin America, the session highlighted the gap between oil-price strength and producer-equity performance. Brazil and Guyana remain supply-growth stories; Argentina is a shale call option; Mexico and Venezuela are constrained state-run systems unable to respond quickly to higher prices.
The board tells a selective market: geopolitical fear lifted crude, but not every producer leveraged that move into share gains.
What matters today. The Strait of Hormuz threat is re-pricing supply risk, but Latin American producers are moving on their own corporate and political stories rather than simply tracking the barrel.
01 The session in one read
Crude benchmarks climbed to three-week highs on Tuesday after Iran said it would adopt a more offensive stance and keep the Strait of Hormuz closed, while the United States ruled out extending a ceasefire. Brent and WTI both settled at their strongest since July 24, driven by renewed fear that a key shipping chokepoint could be closed to tanker traffic.
The futures market moved more forcefully than the equity proxies tracking it. The USO exchange-traded fund, which follows front-month WTI futures, ended at US$130.66, a rise of 0.28%, a muted equity-market echo of the sharpening geopolitical alarm.
Tuesday’s rally was narrow and emotional, built on Iran’s rhetoric and American refusal to extend the ceasefire rather than any fresh physical supply loss. The diverging producer moves, Petrobras down, YPF sharply lower, Ecopetrol flat, suggest equity investors are discriminating by company story, not just crude direction.
The variable to watch is whether the Hormuz closure threat persists long enough to drag producer equities back into line with the stronger crude tape.
02 The board
The price board showed a split between the crude tracker and the Latin American producers. Petrobras closed down 0.38% at US$18.18, while YPF fell 3.83% to US$50.68, the sharpest move among the tracked regional names.
Ecopetrol was the quietest actor, up 0.06% to US$17.68, suggesting the Colombian state producer neither benefited from the crude jump nor suffered the profit-taking that hit YPF after its strong Monday run.
| Asset | Level | Change |
|---|---|---|
| WTI crude (USO) | US$130.66 | +0.28% |
| Petrobras | US$18.18 | -0.38% |
| Ecopetrol | US$17.68 | +0.06% |
| YPF | US$50.68 | -3.83% |
Source: RT close, 2026-08-18. Where a commodity has no spot feed, an exchange-traded tracker or leading producer is shown as a labelled proxy.
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Latin America — Cross-Market Board
| Instrument | Last | Change | YoY | Prev. | High | Low | Volume |
|---|---|---|---|---|---|---|---|
| IBOV | 166,334.86 | -0.27% | +21.85% | 166,783.57 | 168,310 | 167,142 | — |
| IPSA | 11,186.57 | +0.34% | — | 11,148.13 | 11,210 | 10,984 | 1,513,213,483 |
| IPC MEX | 64,301.04 | +0.07% | +12.17% | 64,254.98 | 66,121 | 65,405 | 108,886,187 |
| MERVAL | 2,891,651 | -1.89% | +30.51% | 3,022,485 | 3,042,365 | 2,991,150 | — |
| COLCAP | 2,461.23 | +0.36% | — | 9.04 | 9.05 | 9.02 | 4,133 |
| BVL PERÚ | 58,401.58 | -1.35% | — | — | — | — | — |
| USD/BRL | 5.16 | +0.01% | -5.13% | 5.16 | 5.18 | 5.14 | — |
| EUR/BRL | 5.95 | +1.01% | -5.83% | 5.89 | 5.98 | 5.94 | — |
| USD/MXN | 17.06 | -0.24% | -8.58% | 17.10 | 17.08 | 17.01 | — |
| USD/CLP | 913.98 | +0.04% | -5.67% | 913.65 | 915.11 | 906.68 | — |
| USD/COP | 3,140 | +0.03% | -22.04% | 3,139 | 3,141 | 3,105 | — |
| USD/PEN | 3.36 | -0.66% | -4.82% | 3.38 | 3.38 | 3.35 | — |
| USD/ARS | 1,493 | +0.10% | +12.96% | 1,491 | 1,494 | 1,480 | — |
| USD/UYU | 40.27 | +1.24% | +1.80% | 39.77 | 40.27 | 40.23 | — |
| USD/PYG | 5,939 | +1.68% | -19.54% | 5,841 | 5,939 | 5,925 | — |
| USD/BOB | 11.64 | -0.76% | +72.04% | 11.73 | 11.72 | 11.64 | — |
| USD/DOP | 58.34 | +1.25% | -3.44% | 57.62 | 58.34 | 58.04 | — |
| USD/CRC | 445.92 | +0.89% | -9.71% | 441.97 | 448.50 | 445.92 | — |
03 What moved it
The immediate trigger was geopolitical: Iran declared the Strait of Hormuz would remain closed and promised a more offensive footing, while Washington said the ceasefire would not be extended. An attack on a merchant ship in the strait and the expiry of a 60-day US-Iran memorandum added to the sense that a major oil transit route is at risk.
That fear translated into higher paper prices for the second session running. But the API inventory data offered a softer counterweight, with US crude stocks estimated to have fallen by 328,000 barrels last week, far smaller than the prior week’s 9.072-million-barrel build.
Refiners are still the market’s quiet winners: global refinery throughput in July ran nearly 5 million barrels per day below the year-earlier level, keeping refined-fuel margins rich even as crude has settled well below its wartime peak.
04 The Latin American read
Brazil’s state-controlled Petrobras confirmed oil in the Morpho well in ultra-deep waters off Amapá, in the Foz do Amazonas basin, but warned it cannot yet estimate volumes or commercial viability. The announcement is a long-dated exploration signal rather than a near-term output story, which helps explain the shares’ 0.38% slip despite stronger crude.
Brazil’s pre-salt remains the region’s main deepwater magnet: 19 oil companies have been cleared to bid for partnerships with the Brazilian state, including Spain’s Repsol and Colombia’s Ecopetrol. Guyana’s Exxon-led Stabroek block continues to set the offshore growth benchmark even without a local listed proxy.
Argentina’s YPF is the volatility leader. It fell 3.83% to US$50.68 after Monday’s 5.29% surge, with traders locking in gains around the Vaca Muerta shale story and YPF’s longer-term plan to drill offshore Uruguay starting late 2027 or early 2028.
Mexico’s Pemex and Venezuela’s PDVSA remain constrained state models. Higher oil prices help their revenue lines, but neither can quickly add barrels the way Brazil or Guyana can.
05 The names to watch
YPF is the name that moves most violently on shale sentiment and global demand hopes; Tuesday’s 3.83% drop showed how quickly the Vaca Muerta premium can unwind. The upcoming trading sessions will test whether Monday’s enthusiastic buyers hold or continue trimming.
Petrobras carries two stories at once: the confirmed Morpho discovery adds frontier optionality, while the pre-salt auction list of 19 bidders signals that international capital still sees value in Brazil’s deepwater system despite local fiscal and political noise.
Ecopetrol is the reluctant observer, barely moving on a day of crude strength, but it appears on the Brazilian pre-salt bidder list, showing a state producer seeking regional growth beyond mature Colombian fields.
The USO fund remains the cleanest way foreign readers can track the geopolitical price impulse without single-company risk, and its modest 0.28% gain suggests equity markets are treading carefully around the Iran headlines.
06 The outlook
The market’s direction now hinges on whether Tehran’s Hormuz threat hardens into action or fades into rhetoric. The small 328,000-barrel US crude draw is a weak bullish add-on, while refined-product scarcity continues to support most parts of the complex.
For Latin America, the test is whether producer equities catch up with the crude tape if prices keep climbing, or whether profit-taking in YPF spreads to Petrobras and Ecopetrol. Watch for any concrete movement through Hormuz, which would be the fastest repricing catalyst.
07 What to watch
- Strait of Hormuz shipping traffic: any attack or actual closure would sharply reprice crude and put USO, Petrobras and YPF back into synchronised gains.
- YPF post-surge consolidation: after falling 3.83% on Tuesday, further selling would suggest the Vaca Muerta rally is cooling rather than merely pausing.
- Petrobras Morpho follow-up: any new estimate of volumes or commercial viability could turn the Foz do Amazonas story from exploration hope into reserve news.
- Brazil pre-salt auction pricing: with 19 bidders lined up, the bonus levels and partnership terms will signal how much foreign capital still chases Brazilian deepwater.
Frequently Asked Questions
Why did oil rise on Tuesday?
Iran said the Strait of Hormuz would remain closed and the US ruled out extending the ceasefire, pushing Brent and WTI to three-week highs.
What is USO and why use it?
USO is an exchange-traded fund that tracks front-month WTI crude futures, offering investors a liquid equity proxy for US oil prices.
Why did YPF fall while crude rose?
YPF fell 3.83% to US$50.68 as traders took profits after Monday’s 5.29% Vaca Muerta-driven surge, even as crude strengthened.
What is Brazil’s pre-salt and why does it matter?
It is Brazil’s main deepwater oil reserve system, and 19 companies including Repsol and Ecopetrol have been cleared to bid in the next partnership auction.
This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error
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