Ms Truss made the announcement this afternoon after just under two months in post.

Speaking in Downing Street, Ms Truss said: “This morning I met the chairman of the 1922 Committee, Sir Graham Brady.

“We’ve agreed that there will be a leadership election to be completed within the next week.

“This will ensure that we remain on a path to deliver our fiscal plan and maintain our country’s economic stability and national security.

“I will remain as Prime Minister until a successor has been chosen.

“Thank you

Is Liz Truss the shortest serving Prime Minister?

The person who previously held the title is the Tory statesman George Canning, who spent 118 full days as prime minister in 1827 before dying in office from ill health.

Ms Truss would have had to remain Prime Minister until January 3, 2023, to pass Mr Canning.

There have been several prime ministers who for various reasons failed to last a year in the job.

They include two Conservative PMs in the past 100 years: Andrew Bonar Law, who clocked up 211 days from 1922 to 1923 before resigning due to poor health, and Alec Douglas-Home, who managed 364 days in 1963-64 until losing a general election.

During the 18th and early 19th century it was not unusual for prime ministers to serve for only one or two years, or to do the job for a short spell on several separate occasions.