Gilt Yields Surge as Tech and Energy Diverge

Today’s UK capital markets narrative is defined by a sharp divergence between geopolitical relief and domestic fiscal anxiety, with the FTSE 100 closing down 1.4% as investors grappled with surging gilt yields and energy sector volatility. The most significant market mover was the UK government’s borrowing costs, where 30-year gilt yields hit a 28-year high of nearly 5.8%, driven by deep-seated concerns over the Labour government’s fiscal management and inflationary pressures. This bond rout, which sparked calls for the Bank of England to slow its quantitative easing unwinding, weighed heavily on the broader index, overshadowing positive sentiment from the US markets which hit record highs. While oil prices initially spiked on Middle East conflict fears, pushing Shell to report a doubling of underlying earnings to $6.92 billion, the subsequent hope of a US-Iran peace deal caused a rapid sell-off in energy stocks and a spike in the pound, creating a challenging environment for exporters and domestic growth alike.

In the technology and semiconductor space, the focus remains intensely on Arm Holdings, whose stock performance highlighted the complex reality of the current AI boom. Despite reporting fiscal fourth-quarter profits that topped estimates and forecasting revenue growth driven by surging demand for AI data center CPUs, the share price faced significant headwinds. The market’s reaction was a classic case of “buy the rumor, sell the news,” as investors digested warnings regarding weakness in the smartphone market and, more critically, a lack of secured manufacturing capacity to meet the exploding demand for its new chip architectures. This supply-side constraint serves as a stark reminder that while the design capability of UK tech giants is world-class, the physical bottlenecks in the global semiconductor supply chain remain a critical risk factor for valuation.

The defence and industrial sectors offered a counter-narrative of resilience, with BAE Systems reaffirming its 2026 earnings growth guidance of 9% to 11% amidst a backdrop of escalating global defence spending. The ongoing conflicts in the Middle East and Ukraine have directly translated into a surge in order inflows, allowing the UK’s largest defence contractor to maintain a robust outlook despite the broader macroeconomic turbulence. Complementing this, Morgan Advanced Materials reiterated its full-year guidance, signaling that specialist manufacturers are navigating the current volatility with stability. Meanwhile, the private markets infrastructure saw a notable expansion as StepStone Group launched evergreen strategies on the LSEG’s Digital Markets Infrastructure, bridging the gap between traditional asset management and digital trading capabilities.

Looking ahead, the defining stories of the day were the clash between geopolitical de-escalation hopes and the hard reality of UK sovereign debt costs, alongside the mixed signals from the AI semiconductor sector. Markets closed with a clear preference for defensive positioning, as the FTSE 100 retreated on the back of banking and energy losses, while the FTSE 250 struggled against a stronger pound and political uncertainty ahead of local elections. Investors should watch tomorrow’s UK local election results closely, as the outcome could either validate or exacerbate the current fears regarding fiscal stability, potentially triggering further volatility in the gilt market and influencing the Bank of England’s future rate trajectory.