Why Citi Slashed Its 2026 Brent Crude Forecast After the U.S.-Iran Deal

Oil markets lurched downward on Monday, June 15, after the United States and Iran confirmed a memorandum of understanding (MoU) to end their months-long conflict and reopen the Strait of Hormuz . The deal immediately rewrote price expectations: Citigroup, which just weeks earlier was warning oil could spike to $150 per barrel, took an axe to its Brent crude forecasts . But the gap between a signed piece of paper and tankers moving freely through the world's most critical oil chokepoint is vast. Here is what changed, why, and what uncertainties still hang over the energy market.

What triggered Citi's forecast cut

Citi's rapid revision was a direct response to the U.S.-Iran MoU, which the bank believes will normalize trade flows through the Strait of Hormuz and restart Iranian oil exports . The strait had been effectively blocked since late February, causing the largest disruption to global energy supply since the 1970s and pushing Brent crude above $126 per barrel at its peak . The new diplomatic framework removes, at least on paper, the central supply bottleneck that had defined oil markets for months.

New forecasts vs. prior forecasts

The scale of Citi's downgrade reflects how quickly conviction around a supply recovery solidified. On April 26, the bank had raised its base-case forecasts to $95 per barrel for Q3 and $80 for Q4, and it warned of a 30% probability bull case sending prices to $150 if the strait stayed shut through June . On June 15, those numbers were torn up .

Period	Prior forecast (late April 2026)	New forecast (June 15, 2026)	Change
Q3 2026	$95/bbl	$75/bbl	−$20
Q4 2026	$80/bbl	$70/bbl	−$10
Full-year 2027	$80/bbl	$65/bbl	−$15

The 2027 forecast of $65 per barrel brings Citi close to what it had previously considered a bear-case scenario, essentially betting that the diplomatic opening will translate into a rapid, sustained resumption of oil flows .

How markets reacted to the U.S.-Iran framework

The immediate market response was a classic risk-on rotation. Brent crude fell roughly 4% to 5% on June 15, settling at its lowest level in three months near $83 per barrel . At the worst intraday point, some reports put the decline near 11% before prices stabilized . West Texas Intermediate also dropped more than 5% .

The relief rally in equities was equally sharp, with U.S. stock indices trading near all-time highs as investors bet that the worst energy supply crisis in modern market history was easing . European wholesale gas prices fell 6% in sympathy .

The next day, however, oil rebounded slightly as traders absorbed the deal's vague language and the hard reality that physical supply restoration would not happen overnight .

The long road to physical supply recovery

A market that prices in peace can still face months of physical tightness. Several obstacles stand between the MoU and a fully functioning Strait of Hormuz .

• Logistical backlog. Even after the strait formally reopens, rebuilding commercial shipping schedules, insurance frameworks, and port logistics will take months, not weeks . S&P Global Commodity Insights projects that full supply normalization will extend through summer 2027 .
• Mine clearing and recertification. Naval mines reportedly deployed in the strait must be cleared, and ship insurers will need to recertify the waterway as safe for commercial transit .
• Buyer adaptation. Many crude buyers have already locked in alternative supply routes and term contracts, meaning there will be no instantaneous snapback to pre-war flow patterns .
• Supply deficit legacy. The cumulative supply disruption from the crisis exceeded 500 million barrels, and Saudi Aramco's CEO warned in May that even an immediate reopening would not produce market normalization until 2027 .

The 60-day window and unresolved geopolitical risks

The MoU is a preliminary framework, not a final settlement. It establishes a 60-day cessation of hostilities during which Washington and Tehran must negotiate a permanent agreement—including the status of Iran's enriched uranium stockpile . If those talks collapse, the strait could be closed again.

Several specific uncertainties are worth watching:

• Nuclear negotiations deferred. Iran has insisted the MoU does not include nuclear commitments, and those discussions are expected to proceed on a separate, slower track with no firm deadline . Failure to resolve nuclear disputes could unravel the entire arrangement.
• Passage fees unresolved. Iran has offered charge-free transit for the initial 60-day period, but there is no long-term agreement on fees or on Iran's role in managing the waterway—an ambiguity that could spark future disputes .
• Sanctions and asset release. The deal reportedly involves lifting U.S. oil sanctions and unfreezing Iranian assets, but the mechanics and sequencing remain unclear, potentially delaying Iran's return to full export capacity .
• Geopolitical spillover. An ongoing Israeli offensive in Lebanon could extend regional hostilities and derail the U.S.-Iran understanding, a risk flagged by the Associated Press and other outlets .
• No formal peace treaty. The MoU is an interim memorandum, not a permanent peace treaty. U.S. officials have acknowledged that finalizing such an accord could take months—or longer—if past negotiations with Iran are any guide .

What to watch next

The oil market is now caught between two narratives: the powerful disinflationary pull of a diplomatic breakthrough and the stubborn reality that the Strait of Hormuz will not function normally for months. Citi's rapid forecast cut captures the directional shift, but the wide range of outcomes—from a swift return to $65 oil to a possible re-blockade that sends prices soaring again—means volatility is unlikely to fade quickly. The 60-day countdown has begun.