Rachel Reeves landed in Washington on Tuesday with an unwelcome piece of luggage: the International Monetary Fund’s ruling that Britain is the biggest economic casualty of the Iran war among the world’s richest nations.
The Fund’s spring forecast, presented to mark the Chancellor’s arrival at IMF and World Bank meetings, cut the UK’s growth forecast for 2026 by 0.5 percentage points, the biggest cut made to a G7 economy since its January outlook. Inflation is now expected to rise to 4 percent while unemployment is heading toward its highest level in more than a decade.
For small and medium-sized businesses, which make up two-thirds of Britain’s private sector workforce, the figures spell grim pressure: weaker consumer demand, stubborn cost inflation and a Treasury with little scope to soften the blow.
The United Kingdom entered the conflict already behind. Growth was sluggish long before the first rockets flew, and businesses and households hunkered down ahead of last fall’s budget proposal amid a fog of tax speculation that dampened activity on high streets and boardrooms alike.
Pierre-Olivier Gourinchas, the IMF’s economic adviser, pointed to what he called a “shadow effect” stemming from this weaker momentum, a drag the fund believes will impact performance next year. The Chancellor strongly rejects this diagnosis, arguing that Labor inherited a damaged economy from the Conservatives and has since built a more solid foundation. But the data is unsympathetic: British households were already struggling with the highest inflation rate in the G7 before a single Iranian oil facility was attacked.
The deeper problem is energy. The Iran conflict has shaken global supplies in the most severe way since the oil crises of the 1970s, and Britain’s mixed gas energy mix leaves the country unusually vulnerable. Although much of the country’s gas is produced domestically, imported cargoes are bought at greatly inflated wholesale prices, and with gas setting the limit price for British electricity, the pain quickly spreads from the terminal to the meter.
“Gas prices are more likely to be transmitted, if you will, to wholesale energy prices,” Gourinchas noted, noting that household bills are only temporarily cushioned by existing government measures.
Reeves used her Washington platform to push for de-escalation while also sharpening her criticism of Donald Trump’s decision to continue the war against Iran. The political calculation is clear. With public finances under pressure from increased debt and stubbornly high borrowing costs, its fiscal space is razor-thin and Labor is trailing in the polls as May’s local elections face a tough test.
Treasury insiders expect short-term, targeted relief measures rather than a full-scale spending explosion, exactly the recipe that the IMF itself has advocated. Anything more expansive risks unsettling the gilt market and destroying the hard-earned credibility that Reeves has tried to build over the past year.
For the British business community, the more important question is what happens when the immediate crisis subsides. Arming the country against the next energy shock will require a far more aggressive push into domestic renewable power generation, grid expansion and the kind of supply-side reforms that unlock large-scale private investment.
SME owners hoping for relief will be closely watching two pressure points: whether the promised targeted support reaches smaller businesses facing skyrocketing input costs, and whether the long-promised industrial strategy finally delivers the cheaper, home-grown electricity that British manufacturers have demanded for almost a decade.
Reeves returns from Washington with the IMF’s blessing for her fiscal restraint, but also with a blunt warning that at current levels the UK will be at the bottom of the G7 rankings in 2026. For a chancellor who doesn’t have the necessary political capital anyway, it’s a judgment she can hardly let rest.
