UK Stocks Fall Sharply as Oil Prices Surge Past $100

London's FTSE 100 index experienced its most significant slump in two months on September 9, 2026, as oil prices climbed back above $100 a barrel. The index closed down 1.3 percent, or 141.6 points, at 10,670.06, marking its lowest level in nearly seven weeks. This decline was the sharpest since early July.

The surge in Brent crude to as high as $101.58 a barrel was fueled by escalating hostilities in the Middle East, which heightened concerns over global oil supplies. Similar downturns were observed in European markets, with Germany's Dax falling 1.7 percent and France's Cac down 1.9 percent. Wall Street also registered losses.

"Higher oil prices mean higher inflation expectations, which also means higher chances of interest rate hikes and higher bond yields," said Kiran Ganesh, global head of investment communications at UBS. "So oil is the key driver, and it’s having a compounding negative impact on equities over the past few days."

Government borrowing costs in the UK also increased. The yield on 10-year gilts, a key indicator of the UK's borrowing costs, approached 5.27 percent, nearing a 19-year high. This followed a record 5.82 percent interest rate paid on the sale of £4.25 billion of 30-year bonds just days prior, the highest yield since 1998.

"The difference between a $99.99 and $100-per-barrel oil price may not mean much in practical terms but it is ringing major alarm bells for investors," said Danni Hewson, head of financial analysis at AJ Bell. "Brent crude prices ticking over this mark for the first time since July is concentrating minds on mounting inflationary risks and the implications for borrowing costs."

The Bank of England is anticipated to maintain current interest rates at its upcoming meeting, though further increases are expected later in the year. Meanwhile, the European Central Bank might raise rates in the eurozone on the same day the FTSE 100 fell. "There is a risk that the ECB perhaps overreacts to the move in oil prices, and then that causes a more negative impact on the rest of the economy," Ganesh noted.