The pound fell 0.2% to $1.321, extending losses that have seen the currency decline around 3% since political pressure on Starmer intensified earlier this year.

Investor attention has increasingly shifted toward the possibility of a leadership transition after Andy Burnham, the former mayor of Greater Manchester, returned to Parliament following a decisive electoral victory on Friday, fueling speculation he could emerge as Starmer’s successor.

Market participants said uncertainty over future fiscal policy was becoming a key concern, particularly given Britain’s already fragile public finances and elevated borrowing costs.

“The most important question relates to Mr. Burnham’s approach to fiscal policy, his pick of Chancellor and whether he will stick to the fiscal rules,” Nomura economist George Buckley said.

Britain currently faces the highest medium-term borrowing costs among Group of Seven economies, reflecting a combination of high public debt, rising interest payments, weak economic growth and increasing spending pressures, including defense expenditure.

The options market indicated investors were paying a premium to protect against larger swings in sterling over the coming weeks, suggesting expectations of heightened political and financial market volatility.

Particular attention remains focused on the government bond market. Benchmark gilt yields hovered around 4.85%, close to their highest levels since the global financial crisis, increasing the cost of government borrowing and amplifying investor sensitivity to fiscal developments.

Analysts said the prospect of a new leadership team has prompted scrutiny of whether existing fiscal discipline would be maintained. Burnham has publicly stated that he supports the fiscal framework championed by Finance Minister Rachel Reeves, but investors remain cautious about how future spending commitments would be financed.

“Burnham has said that he would respect fiscal rules. However, it is not obvious where the money for any additional spending will come from,” Jefferies strategist Mohit Kumar said.

Kumar noted that tax levels were already elevated and argued that projected efficiency savings often proved difficult to achieve in practice.

Reflecting those concerns, Jefferies said it remained underweight sterling and continued to avoid longer-dated British government bonds, anticipating further volatility in the gilt market in the days ahead.

The latest market moves underscore investor sensitivity to political developments in Britain, where repeated leadership changes and concerns over long-term fiscal sustainability have contributed to heightened volatility across currency and bond markets since the country’s 2016 vote to leave the European Union.