UK stock markets opened lower on Monday as diplomatic efforts between the United States and Iran unraveled over the weekend and the U.S. President Donald Trump warned of an "immediate" blockade of the Strait of Hormuz. The diplomatic setback lifted oil prices and swung investor flows toward energy companies, while travel-related equities and broader European bourses lost ground.
By 12:26 GMT the FTSE 100 had slipped 0.4% and the British pound was down 0.3% versus the dollar at 1.3422. Continental European markets also weakened, with Germany's DAX off 1.4% and France's CAC 40 down about 1%.
In a live broadcast on BBC Radio 5 Live, British Prime Minister Keir Starmer stated that the UK would not take part in the war with Iran or join a blockade of the Strait of Hormuz. "We9re not supporting the blockade," he said, and he emphasised the importance of getting the strait reopened to maritime traffic.
Energy and commodity-linked moves
Global oil and gas shares climbed as crude returned above the $100-per-barrel threshold, driven by heightened supply-risk fears after the collapse of talks between Washington and Tehran and U.S. naval action to block maritime traffic to and from Iran through the Strait of Hormuz. Brent crude surged 8% to $102.78 a barrel, as of 05:00 ET.
U.S. energy majors saw notable premarket gains: ExxonMobil (NYSE:XOM) and Chevron (NYSE:CVX) each rose by more than 2%, ConocoPhillips (NYSE:COP) gained about 3.4%, and Occidental Petroleum (NYSE:OXY) advanced roughly 3.1%.
In London and on continental exchanges, European energy groups also benefited from the price move. BP (LON:BP) and Shell (LON:SHEL) climbed around 1.4% each in London trading, TotalEnergies (EPA:TTEF) edged up about 1.3%, and Repsol (BME:REP) added roughly 2%.
Airlines and travel sector under pressure
The steep rise in jet fuel and crude weighed heavily on airline shares across Europe, with sector declines ranging between 2.7% and 7.7% as higher oil prices pressured operating costs. Carriers affected included Ryanair (LON:RYA), IAG (LON:ICAG), Lufthansa (ETR:LHAG), Air France-KLM (EPA:AIRF), easyJet (LON:EZJ) and Wizz Air (LON:WIZZ).
Analysts at Bernstein adjusted their ratings in response to the changed fuel outlook, upgrading Ryanair to outperform while downgrading easyJet and Wizz Air to market-perform. The firm cited about a $200 per metric tonne rise in the European jet fuel forward curve following the Iran conflict, a shift that its analysts said has fundamentally altered the sector's earnings outlook.
UK corporate headlines
Vistry Group (LON:VTYV) shares fell 4.1% after the company announced the immediate appointment of Adam Daniels as Chief Executive Officer and Executive Director. Daniels, who has been Executive Chair of one of Vistry's two largest operating divisions and is a member of the group's Executive Leadership Team, replaces Greg Fitzgerald, who is stepping down as Executive Chair and CEO by mutual agreement.
Payments firm Wise (LON:WISEa) posted a notable rise, with shares jumping more than 5% after reporting strong quarterly metrics. For Q4 FY2026 Wise said cross-border volumes rose 27% year-on-year to A349.4 billion from A339.1 billion a year earlier, and underlying income increased 24% to A3435.3 million from A3350.4 million in Q4 FY25. The company is progressing with a planned U.S. stock market listing scheduled for May 11.
RBC Capital Markets revised its view on WH Smith (LON:SMWH), downgrading the retailer to sector perform from outperform and trimming its price target to 650p from 675p. RBC said it had lowered FY26-27 pre-tax profit forecasts by 3-4%, leaving its estimates slightly below the bottom end of WH Smith's own A3100-115 million guidance range.
Policy and macro commentary
The Bank of England released new and updated guidance on how the UK's resolution regime could be implemented if a bank failure occurred. The guidance is intended to ensure banks can fail without disrupting critical services such as payments and access to deposits and without relying on public funds.
Major broker UBS cut its UK growth forecast for 2026 to 0.6% from 1.1%. In a note UBS said elevated energy prices resulting from the Iran conflict are expected to lift inflation and squeeze consumer spending and corporate margins. The downgrade was issued amid a two-week ceasefire in Iran; UBS noted that oil prices were up roughly 40% and wholesale gas prices about 50% higher since the start of the conflict.
The market reaction on Monday highlighted how heightened geopolitical risk can quickly reweight sector performance - lifting energy and commodities plays while pressuring travel, retail and broader domestic demand-sensitive variables.