The U.K. is getting a new prime minister, but bond investors are really in charge and ‘hyper-reactive,’ Wall Street veteran says

Andy Burnham will become the United Kingdom’s seventh prime minister in a decade on Monday, and must face the consequences of a bond market fiasco from three administrations ago.

A report from the International Monetary Fund this week highlighted the baggage that still hangs over the world’s fifth largest economy: a 2022 budget with unfunded spending hikes and tax cuts that sparked an investor revolt leading to the ouster of Liz Truss as premier after only 44 days.

“Market feedback suggests that the September 2022 gilt market turmoil marked a structural shift in the fragility of the gilt market,” it said. “Policy credibility and predictability are key to strengthening market confidence and reversing the impact of the September 2022 episode.”

The IMF added that foreign investors have become bigger participants in the U.K. bond market, estimating that global factors accounted for 60%-90% of the variation in yields between 2020 and 2026.

That could leave the U.K. more vulnerable to volatile capital flows and “fast money” that’s more price sensitive, the report warned.

Burnham will likely chafe under that kind of influence. He complained in September 2025 that “We’ve got to get beyond this thing of being in hock to the bond market.”