Sterling in danger zone as BBH flags fiscal credibility risk

Brown Brothers Harriman (BBH) warns that fiscal credibility keeps the British pound in a vulnerable position, according to the bank's latest note. UK government debt dynamics remain the central risk for sterling, with no immediate catalyst to ease the pressure. The assessment comes after the 2022 mini-budget turmoil reset market sensitivity to any signal that fiscal discipline is slipping. Even after the current government's fiscal reset under Chancellor Rachel Reeves, bond vigilantes remain active. The gilt market still prices in a risk premium that keeps yields elevated relative to other developed economies, and that premium acts as a persistent drag on the pound.

The Gilt Premium and the Sterling Drag

The simple read is that higher gilt yields should support the pound. The better market read looks at why yields are rising. When the sovereign risk premium drives yields higher – not stronger growth or tighter Bank of England policy – the effect on sterling reverses quickly. Global investors demand compensation for default or inflation risk, not an improving return on capital.

That distinction shows up in the GBP/USD cross. Sterling has struggled to sustain moves above 1.27 in recent weeks. The pair remains in a narrow range, with downside risk dominating options pricing. Interest rate differentials vs the US dollar favor the dollar because the Federal Reserve stance is clearer. UK fiscal worries complicate the BoE's ability to sound hawkish without triggering a gilt selloff.

What Must Change for a Sterling Recovery