The UK economy has recorded the strongest quarterly growth in a year over the first three months of 2026 with a surprise spurt in activity after the Iran war began, figures show. Gross Domestic Product (GDP) increased by 0.6% between January and March, the Office for National Statistics (ONS) said. This was higher than the 0.5% growth that most economists had been expecting, and marks the strongest since the first quarter of 2025 when GDP also increased by a revised 0.6%. The ONS also said GDP increased by 0.3% in March, surprising economists who had been expecting growth to slow following the onset of the war in the Middle East. Chancellor Rachel Reeves responded to the figures to warn against threatening the “stability” of the economy, amid uncertainty over Sir Keir Starmer’s future as leader. She said in a statement: “The choices I have made as Chancellor mean our economy is in a stronger position as we deal with the costs of the war in Iran. “Now is not the time to put our economic stability at risk.…