FTSE 100 Slides as Oil Tops $103 Amid Strait of Hormuz Standoff
The FTSE 100 fell sharply on 23 April 2026 as Brent crude climbed above $103 per barrel, driven by Iran's seizure of cargo ships in the Strait of Hormuz and warnings from the United States that clearing the waterway of mines could take up to six months.
The blue-chip index closed down 19 points at 10,457, having traded as low as 10,361 during the session, while the mid-cap FTSE 250 dropped 207 points — a decline of 0.9% — as investors fled riskier assets amid the escalating geopolitical crisis.
Background
The Strait of Hormuz, through which approximately 20% of the world's oil supply passes, has become a critical flashpoint in the ongoing Iran-Israel conflict. Iran's Islamic Revolutionary Guard Corps has been conducting operations in the strait, seizing vessels and threatening to disrupt international shipping, sending energy prices sharply higher.
Key Developments
Iran's IRGC seized two cargo ships — the MSC Francesca and the Epaminondas — diverting them to the Iranian coast with their crews detained. Goldman Sachs estimated that approximately 14.5 million barrels per day of Gulf crude output — around 57% of pre-war supply — were offline in April due to precautionary production shutdowns and strategic stock management by producers.
The United States responded with a stern warning, with President Trump ordering the US Navy to "shoot and kill" any Iranian small boats observed deploying mines in the strait. The US also seized a tanker suspected of smuggling Iranian oil and announced it would not renew a short-term authorisation permitting the sale of Iranian oil stranded at sea.
Despite the gloomy market-wide performance, some individual companies delivered strong results. RELX and the London Stock Exchange Group both reported strong earnings, while technology services firm Computacenter lifted its full-year outlook for 2026, citing robust demand from hyperscale clients. However, Sainsbury's shares fell despite beating full-year earnings expectations, as investors were spooked by a cautious outlook.
Why It Matters
Sustained high oil prices feed directly into UK inflation through higher petrol and energy costs, squeezing household budgets and business margins. The FTSE 100's significant exposure to energy and mining stocks means the index is particularly sensitive to commodity price swings, affecting millions of UK pension savers.
What's Next
Markets will be watching closely for any diplomatic breakthrough in the Strait of Hormuz standoff. The Bank of England's 30 April rate decision will also be a key focus, with analysts expecting rates to be held at 3.75%. More at Proactive Investors.
