The pound fell and state borrowing costs rose during a period of uncertainty over the chancellor's future on Wednesday.
During Prime Minister's Questions, Sir Keir Starmer declined to guarantee whether a visibly emotional Rachel Reeves would remain chancellor until the next election following the government's welfare bill U-turn.
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Following his remarks, the value of the pound dropped and government borrowing costs rose, via the interest rate on both 10 and 30-year bonds.
Although market fluctuations are common, there was a reaction following Sir Keir's comments in the Commons - signalling concern among investors of potential changes within the Treasury.
Sterling dropped to a week-long low, hitting $1.35 for the first time since 24 June. The level, however, is still significantly higher than the vast majority of the past year, having come off the near four-year peak reached yesterday.
While a drop against the euro, took the pound to €1.15, a rate not seen since mid-April in the aftermath of President Donald Trump's tariff announcements.
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Meanwhile, the interest rate investors charge to lend money to the government, called the gilt yield, rose on both long-term (30-year) and ten-year bonds.
The UK's benchmark 10-year gilt yield - so-called for the gilt edges that historically lined the paper they were printed on - rose to 4.67%, a high last recorded on 9 June.
And 30-year gilt yields hit 5.45%, a level not seen since 29 May.
Both eased back in the hours following - as a spokesperson for the prime minister attempted to quell speculation about the chancellor's future.
Sky News understands the prime minister made clear to the chancellor that she has his "complete support" and remains integral to his project.
Ms Reeves has committed to self-imposed rules to reduce debt and balance the budget. Speculation around her future led investors to question the government's commitment to balancing the books - and how they would do that.
The questions over her future came after the government scrapped the core money-saving component of its welfare bill, which had been intended to reduce spending in order to meet fiscal rules.
(c) Sky News 2025: How markets reacted to uncertainty over Rachel Reeves's future