RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO/ OSSERVATORE ROMANO" This handout picture released by the Vatican Press Office on August 18, 2011 shows Pope Benedict XVI (L) shaking hands with Spain's Prime Minister Jose Luis Rodriguez Zapatero (R) as he is welcomed by Spain's King Juan Carlos upon his arrival at Barajas airport. Pope Benedict XVI is heading to Madrid for a million-strong Catholic youth festival after Spanish riot police swung batons in clashes with anti-Church protesters over the cost of the six-day World Youth Day festival at a time of economic hardship. AFP PHOTO/ HO/ OSSERVATORE ROMANO

Pope Benedict XVI (R) greets Poland's President Bronislaw Komorowski during a private audience at the Vatican on May 2, 2011. AFP PHOTO / POOL / STEFANO RELLANDINI

Pope Benedict XVI (R) meets Poland's President Bronislaw Komorowski during a private audience at the Vatican on May 2, 2011. AFP PHOTO / POOL / STEFANO RELLANDINI

Pope Benedict XVI (L) greets Poland's President Bronislaw Komorowski during a private audience at the Vatican on May 2, 2011. AFP PHOTO / POOL / STEFANO RELLANDINI

Pope Benedict XVI meets Poland's President Bronislaw Komorowski and his wife Anna during a private audience at the Vatican on May 2, 2011. Photo by ABACAPRESS.COM

Pope Benedict XVI meets Poland's President Bronislaw Komorowski during a private audience at the Vatican on May 2, 2011. Photo by ABACAPRESS.COM

Pope Benedict XVI meets Poland's President Bronislaw Komorowski during a private audience at the Vatican on May 2, 2011. Photo by ABACAPRESS.COM

Pope Benedict XVI (R) and Russia's President Dmitry Medvedev (L) exchange gifts during a private audience on February 17, 2011 at The Vatican. AFP PHOTO / CHRISTOPHE SIMON

Pope Benedict XVI, right, embraces Greece's Orthodox Church Archbishop Christodoulos prior to their meeting in the Pope's private study at the Vatican, Thursday, Dec. 14. 2006. Benedict XVI urged Archbishop Christodoulos to work together to fight growing secularism in Europe. The pope met Christodoulos at the Vatican in what was the archbishop's first visit since he attended the funeral of Pope John Paul II in April 2005. (AP Photo/Danilo Schiavella, pool)

PHOTO: EAST NEWS/AFP Pope Benedict XVI meets Poland President Lech Kaczynski during a private audience in the pontiff's private library at the Vatican, 26 JANUARY 2006. Benedict XVI;Lech Kaczynski * SPECIAL INSTRUCTIONS: * *OBJECT NAME: 56656148PO001_pope*

PHOTO: EAST NEWS/AFP Israeli President Moshe Katsav gives to Pope Benedict XVI three books titled: "Jewish Christian Israel", "Of Bread Alone" and "Cross on the Star of David" at the Vatican, 17 November 2005. "I have the intention to invite Pope Benedict XVI for a state visit to Israel," Katsav told reporters after meetings with Prime Minister Silvio Berlusconi and Foreign Minister Gianfranco Fini durinh his visit to Rome. AFP PHOTO / POOL / PLINIO LEPRI

The wind blows up the gown of Pope Benedict XVI as he walks with German President Horst Koehler, right, on the red carpet during a welcoming ceremony at the airport in Cologne, western Germany, on Thursday, Aug. 18, 2005. Pope Benedict XVI arrived on his first foreign trip as pontiff to take part in the Roman Catholic Church's 20th World Youth Day event in Cologne. (AP Photo/Eckehard Schulz)

PHOTO: EAST NEWS/AFP Pope Benedict XVI greets Polish President Aleksander Kwasniewski in St Peter's basilica after celebrating a mass at the Vatican 24 April 2005. Hundreds of thousands of pilgrims flocked to the Vatican early Sunday for the inaugural mass of Pope Benedict XVI, who was to be installed as the Roman Catholic Church's 265th pope.