U.S. President Barack Obama appeared before the British Parliament Wednesday, telling U.K. politicians that now is the time for American and European leadership. But he also said that leaders must be ready to “change with the times,” a reference to the rising power of new players on the global scene. Still, Obama emphasized that U.S. and British influence remains “indispensable” in international politics. Obama delivered his speech in front of a packed house at Westminster Hall, with former British prime ministers Sir John Major, Tony Blair and Gordon Brown in attendance. He is the first U.S. president to address MPs in the British house of parliament.