Keir Starmer on Monday announced his resignation as British Prime Minister and the Leader of the Labour Party, setting out a timetable for his successor to be elected in the coming weeks and be in place by September. The 63-year-old said he will remain in post until a new leader and PM is elected by the governing party and pledged his "full and unequivocal support" to the new leader to "ensure an orderly handover of power".