Cartel collapse and depressive supply shock. The withdrawal of Saudi Arabia and the UAE of OPEC/OPEC+

The simultaneous withdrawal declaration of Saudi Arabia and the United Arab Emirates from OPEC and OPEC+ (April 28-29, 2026) constitutes the most severe institutional rupture in the oil market since 1985-1986. This study demonstrates that this exit is not a purely bearish signal but rather the prelude to a two-speed structural dislocation:

(i) an immediate bullish price shock dictated by the closure of the Strait of Hormuz and the geopolitical risk premium, and

(ii) a delayed depressive collapse linked to the atomization of the cartel and an imminent market share war.

Our three-state M.-S. Multi-Regime model, calibrated on AIS flows (Steelldy Gotham 3.8), physical ARA inventories (Steelldy 4.2), and the CME futures curve, projects a peak for Brent towards $120-$125/bbl by the end of May 2026 (central scenario, 55%), followed by a depressive drift towards $55-$60/bbl in early 2027. The probability of a price floor at $30-$35/bbl under a total market share war is calculated at 17%. The global economy is not entering a total collapse (8% probability), but is shifting towards a manufacturing recession in the Eurozone and net-importing emerging markets, with moderate stagflation in the United States. The physical dislocation—ARA inventories at 18 days, DVI > 90, kerosene logistical breakdown, and extreme backwardation in refined products—prevents any linear transmission of the paper price decline to the pump.

On April 28, 2026, the UAE (third largest OPEC producer) announced its immediate withdrawal, quickly followed by Saudi Arabia. This triggered an instantaneous oil market reaction: Brent rose 3.1% to $111.60/bbl, and WTI increased 3.7% to $100.09/bbl. This initial surge, counterintuitive for a cartel exit, stems from the realization that OPEC lacks the physical capacity to stabilize a market already fractured by the Iran-US war. OPEC production in March 2026 stood at 20.8 Mb/d (-27%), with the UAE contributing about 1.9 Mb/d (-44%). The de facto closure of the Strait of Hormuz removed approximately 8 Mb/d from the physical market.

This scenario introduces a « Double Shock » thesis, differing from classic oil crises (1973, 1979, 2008) due to its asymmetric temporal nature. The price function P Brent(t) is modeled as the sum of two opposing forces:

Choc 1 (Bullish, short-term) driven by geopolitics and the Hormuz closure, and

Choc 2 (Bearish, medium-term) resulting from OPEC collusion breakdown and a subsequent market share war. Choc 1, lasting from T+0 to T+90 days, is characterized by a geopolitical risk premium of $50–60/bbl. The Hormuz closure and destruction of refining capacity (Kuwait, Bahrain, Port Arthur) create extreme backwardation. Conversely, Choc 2, expected between T+6 and T+18 months, will see the collapse of cartel discipline, where every producer maximizes output, driving prices to a floor of $30–35/bbl.

Monetary and financial context further complicates matters. The FOMC’s 8-4 split on April 30, 2026, maintained monetary uncertainty. The 10-year US Treasury rate at 4.38% and the DXY at 104.2 placed pressure on net oil-importing emerging economies. This financial tightening amplifies the vulnerability of nations with fragile balance of payments (e.g., Egypt, Pakistan, Tunisia, Turkey) in the face of the oil shock.

The MS-GARCH(1,1) model identifies three distinct price regimes:

R1 (Geopolitical, 55% probability, $120-125/bbl by mid-2026 due to potential Strait of Hormuz closure),

R2 (Slipping Transition, 38% probability, $85-95/bbl by Q4 2026 amid ceasefire), and

R3 (Market Share War, 17% probability, \$30-35/bbl by late 2027 from uncompensated OPEC cuts).

he transition matrix shows a low but non-zero chance (0.10) of moving directly from R1 to the depressed R3. The model uses an ARIMA-GARCH structure, calibrated with daily data from 01/01/2025 to 30/04/2026, showing near-unitary persistence (alpha+beta=0.97). M. C. simulations (10,000 paths) over 18 months show a weighted average expected Brent price of approximately $55/bbl by December 2027, with the Central scenario (63% probability, prolonged conflict/dead OPEC) projecting $58/bbl for that date.

Internal Steelldy documents from April 29, 2026, reveal a structural dislocation between the paper market (ICE/NYMEX futures) and the physical market in France and Europe. The apparent decrease in pump prices in France masks a critical physical reality, indicated by the Dislocation Velocity Index (DVI) exceeding the critical threshold of 90 (calculated as Physical Demand / Available Physical Supply). Physical data from ARA confirms this stress: ARA stocks cover only 18 days (vs. a historical 28-30 days), and security stocks at GMS logistics warehouses are down to 3.2 days (vs. 12 days in 2019), with the Proprietary Integrity Index below the critical 0.65. The French pump price is artificially managed by two factors:

(a) the Brent price multiplied by the Gasoil Crack spread and overlaid with tax rates (TIPP + TVA), minus Omega_t, which represents the strategic drawdown of …/… inventories to suppress the physical risk premium (Crack Spread). The exchange rate shift from 1.08 (Feb 27, 2026) to 1.04 (April 1, 2026) contributed an additional +€0.08/L to diesel prices due to direct effect and VAT amplification. The refined products curve exhibits extreme backwardation, signaling immediate scarcity.

(b) The Diesel-Brent Crack Spread is at $48.2/bbl (up 160% from the normal $18.5/bbl in 2025), and the Jet Fuel-Asia Crack Spread is at $52.7/bbl (up 225% from \$16.2/bbl). Logistical stress is extreme, with oil freight (Baltic Tanker) up 41% against the average, and diversions around the Cape of Good Hope up 410% due to route saturation. This market dynamic results in a significant multiplication factor: a -5% change in Brent price translates to a +30.4% change in Gasoil price, meaning the decline in crude oil is completely offset by the surge in refining margins and logistical costs.

Critical Jet A-1 fuel stocks in Europe (ARA) and Singapore are noted. Data analysis combining AIS tracking in the Strait of Hormuz with O… monitoring reveals a 98.5% drop in oil traffic and a 1,770% surge in « ghost ships » (AIS off). ACI Europe forecasts a systemic shortage within three weeks by April 2026. The EU’s Emergency Plan, implemented on April 22, 2026, rests on three pillars: Joint Purchasing (modeled after 2022 gas plans to reduce price variance, but posing a moral hazard risk to natural hedges); suspending the Aviation ETS (offering immediate cash flow relief of about €92/tonne CO2, disproportionately benefiting Full-Service Carriers (FSCs) over Low-Cost Carriers (LCCs)); and establishing strategic reserves modeled as a call option on M+3 kerosene, though this fails to mitigate underlying geopolitical uncertainty. Financially, there is a structural divergence in profitability between FSCs and LCCs. Air France-KLM has hedged substantially (62-87%), managing moderate residual exposure whose risk is partly mitigated by the ETS suspension. Lufthansa, hedging around 80% (gross/diesel), faces high residual exposure and a potential $1 billion loss due to basis mismatch. IAG holds a relatively low residual exposure (62%) benefiting from access to Spanish refineries. Ryanair/easyJet have significant hedges for summer 2026 but high exposure afterward, characterized by razor-thin margins. An institutional trade recommendation is established: Long Air France-KLM versus Short Lufthansa, projecting a 15-20% dispersion over time.

As of April 30, 2026, major indices showed minor fluctuations (Dow Jones -0.57%, S&P 500 -0.04%, Nasdaq 100 slightly positive). Three market anomalies are noted: The historically positive oil-gold correlation turned negative due to rising real rates favoring the dollar over gold ($4,777/oz). Sector correlations show energy up (+8-12%) while transport/heavy industry sectors are down (-5% to -7%), signaling painful growth. The strong DXY (104.2) pressures importer currencies. Critically, the energy supply shock factor now explains 58% of global risk asset variance, overtaking monetary liquidity (32%), marking a regime shift from central bank dominance to physical energy flow control.