Pope Francis prays during a visit to the Western Wall, Judaism's holiest site, in Jerusalem's Old City, earlier this week. While in the Holy Land, the pontiff extended an invitation to the presidents of Israel and the Palestinian Authority to join a prayer meeting at the Vatican. Debbie Hill/UPI/Landov hide caption

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Salam Fayyad passes through an Israeli checkpoint in the West Bank town of Hebron in January. This week, he resigned from his post as prime minister of the Palestinian Authority. Hazem Bader/AFP/Getty Images hide caption

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Palestinian Authority head Mahmoud Abbas delivers a speech in Cairo on May 4, 2011 during a Palestinian unity ceremony. THAER GHANEM/AFP/Getty Images hide caption

itoggle caption THAER GHANEM/AFP/Getty Images