Liz Truss has pulled out of a planned event this afternoon, during which she was due to take questions from journalists.
Downing Street has not given any reason for the canning of the trip to an electronics manufacturer.
It comes as the prime minister fights for her political survival following a torrid week in Westminster that saw her new chancellor, Jeremy Hunt, tear up almost all of the economic policies that brought her into office just six weeks ago.
Ms Truss has apologised for the mistakes she has made and vowed to fight on – but some Tory MPs have expressed doubt over her future.
On Wednesday, backbencher William Wragg revealed he had submitted a letter of no confidence in the PM as he became the sixth Tory MP to publicly call for Ms Truss to go.
He explained that he was extremely displeased with the mini-budget and the current administration’s approach to the economy.
Meanwhile, Tory MP Miriam Cates has said she is not sure whether Liz Truss should lead the party into the next election.
Politics latest: Tory MP says mini-budget left him ‘ashamed’ as he reveals no-confidence letter in PM
Liz Truss ‘completely committed’ to pensions triple lock after chancellor agreed move today
PMQs is a huge test for a prime minister trying to survive from one day to the next
The comments came after the PM faced a make or break PMQs in the commons, during which she said she is “completely committed” to the pensions triple lock.
She made the promise despite Mr Hunt on Monday explicitly ruling out agreeing to any further fiscal pledges ahead of 31 October, when he will announce a medium-term fiscal plan.
Politics live: Tory MP says mini-budget left him ‘personally ashamed’
Ms Truss’ spokesman said the PM and the chancellor had agreed their position on the triple lock today.
The Conservative Party’s 2019 manifesto said it would keep the triple lock in place but that was suspended during the pandemic due to the unusually large rise in average earnings after the government’s furlough scheme ended.
The government earlier this year pledged to restore the triple lock from April 2023, but that was called into question on Monday after the chancellor tore up Kwasi Kwarteng’s mini-budget.