The U.K. will suffer the biggest hit to growth of all of the world's richest economies because of the Iran war, the International Monetary Fund warned on Tuesday. In its latest World Economic Outlook, the IMF projected that the U.K. economy will now grow by just 0.8% in 2026, down from 2025's 1.3% projection. That's the largest cut to growth of any G7 economy, with the U.K. set to lag the U.S., which is projected to grow 2.3% in 2026, as well as the euro area (1.1%), Spain (2.1%), France (0.9%).