[Spain's Prime Minister Mariano Rajoy, France's President Francois Hollande and Portuguese Prime Minister Antonio Costa, from left, pose for a group photo at Lisbon's Belem Cultural Center Saturday, Jan. 28 2017. The leaders of France, Italy, Spain, Greece, Portugal, Malta and Cyprus are attending an informal summit of southern European Union countries. (AP Photo/Armando Franca)]LISBON, Portugal (AP) — French President Francois Hollande has urged Europe to present a united front against populist movements which, he says, are being encouraged by political developments in the United States.