三国協商
He became seriously ill in October 1914 and retired. His successor, Sidney Sonnino, followed the negotiating strategy set by San Giuliano, leading to the secret Treaty of London or London Pact () with the Triple Entente. According to the pact, Italy was to leave the Triple Alliance and join the Triple Entente. Italy was to declare war against Germany and Austria-Hungary within a month in return for territorial concessions at the end of the war.