LONDON — Prime Minister Andy Burnham says politicians “need to be better” in his first speech as Britain’s leader. He is promising to deliver a “circuit breaker” for a system he says has taken wrong turns since the 1980s. Burnham spoke outside 10 Downing St. minutes after he was formally asked to form a government by King Charles III. He succeeded Keir Starmer, on a day when Britain’s political turbulence gave way, at least temporarily, to smooth choreography. Buckingham Palace has released a photo of the two men shaking hands. The ceremony known as “kissing hands” marks the transfer of power. The palace said in a statement that the king “received in audience the Rt. Hon. Andrew Burnham MP and requested him to form a new Administration. The Rt. Hon Andrew Burnham MP accepted The King’s offer and kissed hands upon his appointment as Prime Minister and First Lord of the Treasury.” Burnham is the seventh U.K. prime minister since 2016 in a now well-rehearsed handover after replacing Starmer as leader of the center-left governing Labour Party on Friday. Starmer made a sh