The pound was heading for its worst week in 18 months on Friday as City traders anticipated that the UK prime minister, Keir Starmer, could face a challenge from the Manchester mayor, Andy Burnham, later this year.
After days of uncertainty over Starmer’s future, sterling dropped by about three cents, or 2.2%, during the week to $1.332 on Friday, a five-week low. That would be the largest weekly drop against the US dollar since Donald Trump’s election win in early November 2024.
