In Pics | UK Prime Ministers with shortest tenuresEmbattled British Prime Minister Liz Truss on Thursday resigned as the Conservative Party leader saying she can no longer deliver the mandate she was elected on last month, ending her tenure at 10 Downing Street in London after just 45 days in the job following an open revolt against her chaotic leadership.The 47-year-old outgoing prime minister will stay in charge until her successor is elected by the governing Tory party, with a speeded-up leadership election to be completed by next week.Here's a list of UK Prime Ministers with the shortest tenures in office.