Government borrowing costs have hit their highest level since the 2008 financial crisis as worse-than-expected public finance data compounded a gilt sell-off on worries over soaring inflation and rising interest rates.
Yields on 10-year UK government bonds, also known as gilts, surged above 4.9% at one stage on Friday, up from 4.78% on Thursday and hitting an 18-year high.
Two-year gilts were also up another 11 percentage points at 4.52% on Friday after reaching their highest since January 2025 on Thursday in the worst one-day sell off for the short-dated bonds since the mini-budget market chaos in 2022.
Yields move inversely to prices, meaning they rise as prices fall.
It comes after official figures showed Government borrowing last month jumped unexpectedly to the second highest February level since records began, adding to worries over an impending crisis for the public finances from the Iran war and surging inflation.
The Bank of England held interest rates on Thursday and warned over sharply higher inflation that raised the spectre of possible rate hikes if the war and energy price shock is prolonged.
This had already sent gilt yields racing higher, with the latest public finance statistics adding to the woes and compounding the headache for Chancellor Rachel Reeves as it sent borrowing costs rising.
The Office for National Statistics (ONS) said public sector borrowing stood at £14.3 billion in February, £2.2 billion higher than a year ago and nearly double the £7.4 billion forecast by the UK’s fiscal watchdog, the Office for Budget Responsibility (OBR), in November last year.
It defied expectations for a fall, with most economists expecting borrowing of £8.8 billion for February.
Borrowing for the 11 months of the financial year to March so far stood at £125.9 billion, £11.9 billion less than in the same period the previous year and £1.9 billion below the OBR’s November forecast of £127.8 billion.
Experts cautioned the rising gilts yields will leave Ms Reeves will little firepower to protect households from the impending energy bill shock caused by the war.
Elliott Jordan-Doak, senior UK economist at Pantheon Macroeconomics, said: “We estimate that increases in gilt yields will cut the Chancellor’s headroom by £7.1 billion in 2030/31, if sustained at current levels.”
“The Chancellor will again have to make difficult decisions in the autumn budget unless hostilities end quickly and energy prices subside,” he warned.
Martin Beck, chief economist at WPI Strategy, said public finances would be hit hard if the Iran war is prolonged.
He said: “The shock to energy prices creates a double squeeze for the public finances if it persists.
“Higher oil and gas prices would lift North Sea revenues, and stronger inflation could boost receipts from VAT and frozen tax allowances, but those gains would likely be outweighed by the damage to tax revenues from weaker growth and higher public spending on welfare, debt interest costs, and pressure for fiscal support for households and energy-intensive businesses.”
The data showed Government borrowing in February was pushed up by £13 billion of debt interest payments – a record February high and £5.5 billion up on a year ago – due to increases in Retail Prices Index (RPI) inflation impacting index-linked gilts and the timing of debt interest payments from January that fell into last month.
James Murray, Chief Secretary to the Treasury, said: “Because of the choices we made before the conflict in the Middle East began, we are better prepared for a more volatile world.
“We doubled our headroom and borrowing was forecast to be lower than the G7 average.”
But shadow chancellor Sir Mel Stride said: “Labour have raised taxes by £66 billion but still can’t control borrowing.”
