A supply shock that hurts growth no matter what rates do
When geopolitical fire spreads across distant straits, it finds its way into the homes of ordinary people through the quiet mechanisms of interest rates and mortgage payments. The escalating conflict between the US, Israel, and Iran has closed the Strait of Hormuz to roughly a fifth of the world's oil supply, sending energy prices surging and forcing central banks to abandon the path of relief they had been walking. In Britain, what was nearly certain to be a rate cut in March has become an expectation of frozen or even rising rates through 2026 — a reminder that the financial lives of millions are never fully insulated from the tremors of distant wars.
- A conflict that seemed containable has instead closed one of the world's most critical energy arteries, sending oil to $119 a barrel and shattering market expectations almost overnight.
- UK two-year bond yields surged to their highest single-day jump since the Truss mini-budget crisis, signalling that investors believe tight money — not relief — lies ahead.
- Central banks now face a cruel dilemma: raise rates to fight oil-driven inflation and risk deepening a supply-shock recession, or hold steady and watch prices erode household purchasing power.
- British mortgage lenders have already begun moving — average two-year fixed rates ticked upward on Monday, a small but symbolic reversal of the modest relief homeowners had been counting on.
- The Bank of England, once expected with 80% certainty to cut rates in March, is now forecast to hold at 3.75% through the year, with a possible rise to 4% by next summer.
Financial markets entered Monday morning having lost something they had only recently gained: confidence that borrowing costs in Britain were finally coming down. An 80% probability of a Bank of England rate cut in March had dissolved over the weekend, replaced by the prospect of rates holding steady through 2026 — or even climbing to 4% by next summer.
The cause was the widening Iran-Israel-US conflict and its most immediate economic consequence: the effective closure of the Strait of Hormuz, through which roughly one-fifth of global oil supply passes. Oil prices spiked to $119 a barrel before retreating to $104 after G7 finance ministers signalled they would discuss releasing emergency reserves. But the psychological damage to markets was already done.
UK two-year bond yields jumped to 4.129% from 3.52% in a single session — the most violent move since Liz Truss's mini-budget sent the pound to a record low in 2022. European stock markets fell sharply. The FTSE 100 dropped nearly 2%, Paris's CAC fell 2.5%, and mortgage lenders began quietly raising rates before the day was out.
The deeper problem was the trap it set for central banks. Higher oil prices would stoke inflation across Britain and Europe, both heavily dependent on imported fuel. Yet raising rates to fight that inflation risked compounding the recessionary damage already being done by the supply shock itself. Analysts noted the painful irony: the policy tools designed for demand-driven inflation, like that of 2021, were poorly suited to a crisis rooted in supply disruption.
For British households, the arithmetic was bleak and personal. The modest rate relief many had been anticipating — a gradual easing of mortgage costs after years of pressure — had been postponed indefinitely by events unfolding thousands of miles away. A geopolitical conflict had quietly rewritten the financial plans of millions.
The financial markets woke up on Monday morning to a new reality. What had seemed like a straightforward path toward lower interest rates in Britain—a 80% probability of a rate cut at the Bank of England's March meeting—had evaporated over the weekend. In its place came something harder: the prospect of rates staying put for the rest of the year, and possibly rising to 4% by next summer.
The shift was driven by a single, spreading fear. The conflict between the US, Israel, and Iran had escalated into something both sides appeared willing to sustain for months. That meant the Strait of Hormuz—the narrow passage through which roughly one-fifth of the world's oil supply flows—was effectively closed. Oil prices had spiked to $119 a barrel before settling back to $104 after G7 finance ministers announced they would discuss releasing emergency reserves. But the damage to market sentiment was already done.
By Monday's opening bell, investors had begun pricing in the consequences. UK two-year bond yields, a proxy for future interest rates, jumped to 4.129%, up from 3.52% just days earlier—the largest single-day move since Liz Truss's mini-budget crisis in 2022 sent the pound to a record low. European stock markets fell sharply. London's FTSE 100 dropped nearly 2% before recovering slightly. Paris's CAC fell 2.5%. The message was clear: a supply shock was rippling through the global economy, and central banks would have to respond by keeping money tight rather than loosening it.
For British households already stretched by years of high borrowing costs, the implications were immediate and tangible. Mortgage lenders began raising rates on Monday. The average two-year fixed mortgage rate climbed to 4.87% from 4.84% on Friday. The five-year fix rose to 4.98% from 4.96%. These were small moves in percentage terms, but they signaled a reversal of the modest relief homeowners had been expecting. The Bank of England's monetary policy committee, which had seemed poised to cut rates, was now expected to hold firm—with only two of its nine members likely to vote for a reduction, according to economists at UBS Investment Bank.
The core problem was inflation. Higher oil prices would push up energy costs across Britain and Europe, both heavy importers of fuel. That would squeeze consumer spending and growth. Yet central banks faced a dilemma: if they raised rates in response to inflation, they risked deepening a recession triggered by the supply shock itself. Market analysts noted the irony. Chris Beauchamp, chief market analyst at IG, observed that policymakers seemed to be learning the wrong lessons from 2021, when rate hikes were deployed against demand-driven inflation. This was different—a supply-driven squeeze that would hurt growth regardless of what central banks did. Raising rates aggressively risked making things worse.
The European Central Bank was already being priced by markets to raise rates twice by July, compared with one increase expected before the conflict began. The Bank of England, meanwhile, was now expected to hold at 3.75% through 2026, with the possibility of moving to 4% next June. What had been a year of gradual relief for borrowers had become a year of waiting, uncertainty, and the real possibility of higher costs ahead. The geopolitical shock had rewritten the script for millions of households already struggling with the weight of their mortgages.
Notable Quotes
Policymakers may well have learned the wrong lesson from 2021, and risk setting off a much deeper recession if they get too trigger-happy on rate hikes.— Chris Beauchamp, chief market analyst at IG
Only two of the nine member monetary policy committee are likely to vote for a rate cut that was expected before the crisis.— Anna Titareva, economist at UBS Investment Bank
The Hearth Conversation Another angle on the story
So the market completely reversed course in a matter of days. What changed between Friday and Monday?
The rhetoric from Iran and Trump over the weekend made clear this wasn't going to be a quick skirmish. Both sides signaled they were prepared to fight for months. That meant the Strait of Hormuz would stay closed, oil would stay expensive, and inflation would become the central bank's problem instead of growth.
But higher rates are supposed to fight inflation. Why would that be the wrong move here?
Because this isn't inflation from people spending too much money. It's inflation from a broken supply chain. If you raise rates when the real problem is that oil is scarce, you're just punishing people for something they can't control. You slow the economy without fixing the underlying shortage.
So the Bank of England is trapped.
Exactly. They can hold rates and watch inflation rise, or raise them and risk a deeper recession. Either way, households lose. The mortgage rates are already moving up, and they'll keep moving up as long as oil prices stay high.
How long does this last?
That depends entirely on the conflict. If it settles in weeks, markets will calm down and the Bank might still cut later in the year. If it drags on, we're looking at a year of elevated rates and squeezed living standards.
And the households already struggling with mortgages?
They're the ones who absorb the shock first. A quarter-point rise in mortgage rates doesn't sound like much until you're already stretched thin.