The yield on Britain's benchmark 10-year gilt reached 5.295% on Thursday, its highest level since August 2007, as investors continued to sell government bonds amid a global rise in energy prices and inflation expectations.
Two-year gilt yields also rose to 4.742%, their highest since November 2023, while five-year yields reached 4.828%, the highest since September 2023.
The latest move comes as oil prices remain above $100 a barrel, intensifying concerns that higher energy costs could feed into inflation and delay the easing of monetary policy.
The UK is particularly exposed to the consequences of higher borrowing costs because gilt yields influence financing conditions across the economy. Rising government yields can increase the cost of servicing public debt while also feeding into mortgage rates and corporate borrowing costs.
Despite the pressure, demand for new government debt remained firm at Thursday's auction. Britain's Debt Management Office sold £5 billion of 4.625% May 2030 gilts after receiving £16.2 billion in bids. The bonds were sold at an average yield of 4.786%, the highest for that maturity since October 2023.
The strength of the auction suggests investors continue to see UK government debt as an important asset, even as they demand higher returns for holding it.
The broader concern is the persistence of the global bond sell-off. Investors have been reallocating capital in response to higher energy prices, changing expectations for interest rates and shifts in demand for government securities.
For UK policymakers, higher yields increase the importance of fiscal discipline. A prolonged rise in borrowing costs could constrain future government spending choices and increase the sensitivity of public finances to changes in interest rates.
The immediate trigger may be the energy shock, but the movement in gilts reflects a broader repricing of global financial risk. If oil prices remain elevated, the pressure on UK borrowing costs could persist well beyond the current market episode.
