The UK sold £4.25 billion of 5.375% gilts due in 2056 at a 5.8168% yield, the highest for the longest-dated maturity sold through auction or syndication since the Debt Management Office was created in 1998. Orders exceeded £85 billion, or roughly 20 times the sale size, demonstrating investor demand for elevated UK yields despite rising borrowing costs. Iran-related geopolitical tensions and higher oil prices have revived inflation concerns, prompted markets to price in at least a 25-basis-point Bank of England rate increase by year-end, and narrowed Chancellor John Healey's fiscal room before his first budget. Annual UK debt-interest payments have reached £110 billion, while the Office for Budget Responsibility had previously forecast £109 billion for this year. Long-dated conventional gilts are expected to account for less than 10% of the £246 billion issuance plan as pension-fund demand weakens. The Bank of England may also face pressure to slow quantitative tightening, while France and Germany have joined the broader rise in European long-term yields.