Speaking outside No 10 after being appointed PM by the King at Buckingham Palace, Sir Keir pledged: “My government will serve you, politics can be a force for good.
“The work of change begins immediately, but have no doubt, we will rebuild Britain.”
In his farewell speech outside No 10, Rishi Sunak apologised to unsuccessful Tory candidates and told the public: “I have heard your anger, your disappointment.”
Labour won 412 seats – giving the party a majority of 174 in the new House of Commons. The Conservatives were reduced to a record low for them of 121 MPs, a net fall of 251.
The Liberal Democrats made 63 gains, giving them 71 seats. The SNP suffered a severe defeat, losing 38 seats to stand on nine with one constituency still to declare.
Reform UK won five seats, include leader Nigel Farage’s in Clacton, with the Greens increasing their number of MPs from one to four. Plaid Cymru doubled its number of MPs from two to four.
Within hours of becoming prime minister on Friday, Sir Keir’s appointments to his top team came thick and fast – suggesting plans had been in place for a long time. He is expected to announce more ministerial roles.
