Gilts: Iran Shock Kills the Rate-Cut Dream
Six weeks into the Iran conflict, the damage to UK rate expectations is permanent. The BoE held unanimously at 3.75% in March. Markets that once priced two cuts this year now price fewer than two hikes. That's not a recalibration — it's a complete reversal of the monetary policy outlook.
The 10-year gilt yield traded at 4.80% in early April, retreating from the 4.92% peak on March 27 but still near levels last sustained in 2008. The 30-year sits at 5.47%. A French-owned ship passed through the Strait of Hormuz on April 3, testing the contested waterway, but oil at $111 and US threats of more aggressive strikes on Iran keep energy markets on edge. Every headline moves gilts.
US Treasuries have been comparatively calm. The 10-year fell to 4.31% by April 2, the 2-year to 3.79%. America's energy self-sufficiency insulates its bond market. The UK has no such buffer — and the yield spread between the two tells that story plainly.
Key Takeaways
- UK 10-year gilt yields eased to 4.80% from the 4.92% March peak but remain at their highest sustained level since 2008.
- Rate expectations have completely reversed — markets now price fewer than two BoE rate increases in 2026, abandoning all hope of cuts.
- The UK-US 10-year yield spread of ~45bp reflects the UK's direct energy import exposure, which mechanically raises household bills and inflation.
- Every Iran headline moves gilts more than Treasuries — the asymmetric exposure is structural, driven by 40% gas import dependence.
- Short-duration gilts offer the safest positioning; long-dated bonds are a binary geopolitical bet with significant upside and downside.
The Yield Repricing: Violent but Incomplete
March was one of the steepest monthly sell-offs in European bond history. UK 10-year yields surged 60bp — from 4.23% in late February to 4.92% on March 27. April brought a partial retreat as de-escalation headlines briefly surfaced, with the 10-year settling near 4.75-4.80%. Then Trump's April 2 threat of more strikes sent it back to 4.80%.
The 20-year gilt remains near 5.50%. The 30-year at 5.47% is within touching distance of levels that recall the September 2022 pension crisis. The difference: Liz Truss was a self-inflicted wound the market could price and resolve. The Iran conflict has no visible endpoint.
US Treasuries moved in sympathy but from a lower base and with less volatility. The 10-year at 4.31% on April 2 reflects a yield curve spread of 0.51% — steepening modestly as recession fears compete with inflation repricing. The UK-US 10-year spread narrowed slightly from 50bp to roughly 45bp, but remains elevated.
The gap matters. A 45bp spread over Treasuries means the UK government pays materially more to borrow than the US — despite a smaller economy and lower credit risk tolerance. That premium is the market's stagflation tax on gilts.
Rate Expectations: From Cuts to Hikes
The shift in BoE expectations has been extraordinary. In February, futures priced two 25bp cuts by year-end, with Bank Rate reaching 3.25% by early 2027. By mid-March, after oil breached $100, markets had abandoned cuts entirely. By early April, they price fewer than two rate increases in 2026.
The March 19 vote tells the story. Sarah Breeden and Swati Dhingra — the MPC's most dovish members — abandoned their rate-cut stance in a single meeting. That shift doesn't happen unless the Committee sees a fundamentally different inflation landscape. The BoE's own projections put CPI between 3.0% and 3.5% through mid-2026, with upside risks if energy costs persist.
The Fed funds rate at 3.64% sits below the BoE's 3.75%. The Fed cut six times from 4.33% since mid-2025; the BoE managed four. The divergence widens from here. The Fed can hold and wait — US shale production means oil price spikes don't mechanically raise American household energy bills. The BoE faces a direct pass-through: UK wholesale gas prices up 40% flows into Ofgem's quarterly price cap within months.
Some forecasters have started discussing what was unthinkable in January: a rate hike if CPI reaccelerates above 4%. The gilt curve is already pricing that possibility, which is why short-end yields have risen faster than would be implied by a simple hold-for-longer scenario.
The Energy Transmission Problem
Oil at $111 hits UK bonds harder than US Treasuries (see Gilts: Stagflation Risks) through three channels.
First, direct energy costs. The UK imports 40% of its gas. Every price increase transmits to household bills through Ofgem's cap with a one-to-two quarter lag. Households already stretched by the 2022 energy crisis face another round of increases in Q2-Q3 2026. That feeds into services inflation — restaurants, care homes, transport — the stickiest CPI component.
Second, the exchange rate. Sterling weakens when energy prices spike because the UK's trade balance deteriorates. A weaker pound imports additional inflation on everything from food to manufactured goods.
Third, fiscal knock-on. Higher energy costs increase government spending (benefits, heating support) while reducing tax revenue through weaker consumer spending. Index-linked gilts — roughly a quarter of UK government debt — see their servicing costs rise mechanically with RPI. The UK's fiscal position was already under pressure from the April 6 benefit and pension increases.
The Strait of Hormuz remains the wildcard. The April 3 transit of a French vessel tested the corridor, but shipping insurance premiums have tripled since March. Any sustained closure would send oil significantly higher and gilts into genuine crisis territory.
Global Bond Context
The February bond rally across developed markets was a false dawn. Global yields fell broadly that month — US Treasuries dropped nearly 30bp, UK gilts similar. March reversed all of it for the US and then some for the UK.
The divergence is between central banks with room to manoeuvre and those without. The ECB, with eurozone inflation near target, retains room to cut. The Bank of Japan is slowly normalising but faces no energy import crisis of this magnitude. The BoE stands alone among G7 central banks with both a severe energy import dependency and inflation already 50% above target.
Foreign demand for gilts has weakened through 2025-26. China and Japan reduced sterling-denominated holdings, leaving domestic pension funds and insurers as marginal buyers. Those institutions are price-sensitive and have been forced sellers during volatility — creating the destabilising feedback loop that made September 2022 so dangerous. The DMO's £250 billion gross financing requirement for 2026-27 must clear in this environment.
Positioning for the New Regime
The rate-cutting cycle is dead. Gilt investors must reposition for a hold-or-hike environment that could persist through 2026.
Short-duration gilts (2-5 years) at 4.33% on the 2-year are the cleanest trade. Lower rate sensitivity, adequate income, and first to benefit if the BoE eventually resumes easing — whenever that is. The risk is modest: you're paid 4.33% to wait.
Long-dated gilts (10+ years) are a binary geopolitical bet. If Iran de-escalates and oil drops below $90, the 10-year could retrace to 4.3% — generating 50bp+ of capital gains on duration. If oil sustains above $110 and CPI hits 4%, the 10-year breaches 5%. Only size this trade as much as you can stomach losing on.
Avoid catching the falling knife on 30-year gilts. At 5.47%, the yield is seductive, but duration risk at the long end is extreme. A 25bp move generates roughly 5% price change on a 30-year bond. Wait for either a clear BoE signal or a geopolitical catalyst before extending duration.
The April MPC meeting is the next scheduled catalyst. If the Committee signals it's actively considering a hike, expect the 10-year above 5%. Any de-escalation on Iran — or oil dropping below $100 — would trigger a sharp relief rally in gilts.
Conclusion
The Iran conflict hasn't just delayed BoE rate cuts — it's reversed the entire trajectory. Markets that priced easing now price tightening. Gilt yields near 4.80% reflect a market that has lost confidence in the UK's disinflation narrative and sees the BoE potentially stuck at 3.75% or higher through year-end.
The highest yields since 2008 are an opportunity for patient income investors. But patience requires short duration and tolerance for further volatility. The gilt market's direction from here depends on two things the BoE cannot control: oil prices and the Strait of Hormuz.