Paris Stock Exchange Defies Whit Monday Holiday as Brent Crude Tumbles 5% on Iran Diplomatic Breakthrough Signals

On Monday 25 May 2026, in a notable divergence from major international financial centres, the Paris Stock Exchange (Euronext Paris) was open for trading despite the Whit Monday public holiday in France. The CAC 40 futures gained around 0.7% in early trading according to broker IG data, while Wall Street remained closed for the US Memorial Day and the London Stock Exchange was shut for the British Spring Bank Holiday. Brent crude futures tumbled around 5% to $98.30 per barrel and West Texas Intermediate fell to $91.65 per barrel after US President Donald Trump said over the weekend that talks with Iran to reopen the Strait of Hormuz were “proceeding in an orderly and constructive manner”.

Trump Truth Social drives optimism

The pre-market gains and the sharp drop in crude prices were driven by constructive weekend signals exchanged between Washington and Tehran on resolving the Middle East conflict and a potential reopening of the Strait of Hormuz. On his Truth Social platform, Trump wrote: “Negotiations are proceeding in an orderly and constructive manner, and I have informed my representatives not to rush into a deal, because time is on our side.” Trump had said on Saturday that an agreement to reopen the Strait of Hormuz had been “largely negotiated” and would be announced soon — a relatively measured presidential stance compared with his more bellicose recent statements.

Market indicators on 25 May 2026

The Monday picture combined the rally in European equities with a marked easing of the energy premium that has dominated the macro backdrop since the start of the year. CAC 40 futures gained 0.7% in early trading. Brent crude futures fell about 5% to $98.30/bbl, having lost over 5% over the previous week. WTI fell 4.89% to $91.65/bbl, having shed more than 8% over the past week. The US 10-year Treasury yield traded slightly above 4.49%, the VIX volatility index closed at 16.70 on Friday, and the French OAT 10-year yield remained under pressure at 3.68%. The ECB deposit rate has been maintained at 2.00% since June 2025.

French exchange holiday calendar

Unlike other Euronext exchanges that follow Easter and Whit calendars more closely, the Paris Bourse maintains an operating schedule that keeps several French public holidays as trading days, including 8 May (WWII armistice), 14 May (Ascension Day), 25 May (Whit Monday), 14 July (Bastille Day) and 11 November (WWI armistice). Volumes are traditionally thinner on these dates, but the price discovery mechanism continues to function — a small but visible signal of Paris’s particular role in the European market structure.

Brent has surged over 30% since the war started

Crude prices remain elevated relative to pre-conflict levels: they have surged more than 30% since the joint US-Israeli operation against Iran on 28 February. Iran imposed a de facto blockade of shipping through Hormuz in early March, requiring vessels to obtain Tehran’s authorisation to transit — under threat of attack. The blockade followed US and Israeli airstrikes that killed Supreme Leader Ali Khamenei and other top Iranian leadership. The Strait of Hormuz remains one of the world’s most critical oil chokepoints, with about 20% of global supply transiting the channel before the war.

ECB decision on 5 June looming

The European Central Bank Governing Council meets in Frankfurt on 4-5 June 2026, in what economists describe as one of the most consequential decisions of 2026. After five consecutive maintenance decisions since July 2025, eurozone inflation reaching 3.0% in April 2026 (up from 1.9% in February) is forcing the question of whether the cutting cycle must now reverse. Markets currently price approximately a 60% probability of a 25 basis point hike on 5 June — a significant turning point in European monetary policy if confirmed.

Eurozone inflation dynamics

The April 2026 flash estimate published by Eurostat on 30 April 2026 confirmed annual inflation in the eurozone at 3.0%, up from 2.6% in March and 1.9% in February. The acceleration was primarily driven by a 10.9% year-on-year surge in energy prices — a direct consequence of the US-Iran conflict and Strait of Hormuz disruptions. Core inflation (excluding energy and food) reached 2.4% in March, above the ECB’s 2% target — a development that complicates the simple narrative that the inflation surge is purely an external shock.

Wood Mackenzie scenario: Brent at $80 if Hormuz reopens

If the United States and Iran reach a quick peace deal that reopens the Strait of Hormuz by June, spot Brent prices could ease to around $80 per barrel by the end of 2026, according to consulting firm Wood Mackenzie. In contrast, Citi analysts warn that if the Iranian regime continues to disrupt Strait of Hormuz flows for an extended period, Brent could climb back to $120 per barrel in the near term. The wide divergence between these scenarios is fuelling persistent volatility on European energy stocks.

Outlook for the rest of the week

With most international markets reopening on Tuesday 26 May, attention will shift to whether Friday’s risk-on tone in European equities can be sustained. Investors will closely monitor any further signals from Tehran on Washington’s latest proposal, mediated by Pakistani diplomatic channels. The trajectory of Brent crude and the spread between gilts and bunds will be the key indicators in the coming days — particularly in the run-up to the ECB decision on 5 June.