A Chipper Goodbye: British Prime Minister Hums After Announcing Resignation

— London -- You'd think that resigning as the leader of one of the world's most powerful countries would have left David Cameron less chipper.

But after the leader of the Conservative Party announced today that Wednesday will be his last day as the U.K.'s prime minister, he could be heard humming a tune.

"Thank you very much," he said after making his announcement. As he entered 10 Downing Street, he could be heard humming, "Doo, doo, doo, doo," then adding, "Right ... good."

After calling a referendum on whether the U.K. should stay a member of the European Union, campaigning for the "remain" camp and losing, Cameron announced that he would step down as prime minister but remain in the post until a successor was chosen on September 9. His exit was hastened when Minister of Energy Andrea Leadsom announced today that she was pulling out of the PM race, leaving only one candidate, Home Secretary Theresa May, who will take over from Cameron by Wednesday evening.