"As I said the first time I came to London as President, for the G-20 summit, the days are gone when Roosevelt and Churchill could sit in a room and solve the world's problems over a glass of brandy, although I'm sure that Prime Minister Cameron would agree that some days we could both use a stiff drink. In this century, our joint leadership will require building new partnerships, adapting to new circumstances, and remaking ourselves to meet the demands of a new era."