 He hosted five Conferences for Peace and Christian Civilization in the Palazzo Vecchio from 1952 until 1956 and later in 1967 was elected as the President of the World Federation of United Cities.He also invited the President of the World Zionist Organization Nahum Goldmann to hold the World Jewish Congress in Florence in 1964.In August 1959 he made a visit to Russia and later visited Vietnam in 1965 where he travelled to Ho Chi Minh where he presented an outline for a peace plan.