PHOTO GALLERY: When presidents meet popes

Whenever a U.S. president meets the head of the Catholic Church, it’s always a major news event.

Here’s a look back at some of those historic moments:

In this June 4, 2004, file photo, President George W. Bush is greeted by Pope John Paul II upon their meeting in his private library at the Vatican. | AP file photo

Pope Benedict XVI, center, waves to supporters as President George W. Bush, right, and First Lady Laura Bush look on from a White House balcony overlooking the South Lawn in Washington, D.C. on Wednesday, April 16, 2008. | Bloomberg News

In this June 13, 2008, file photo, Pope Benedict XVI and President George W. Bush walk in the Vatican Gardens during their meeting at the Vatican. | AP file photo

Pope John Paul II and President Bill Clinton clasp hands as they leave the stage after they addressed the crowd in St. Louis on Jan. 26, 1999. | AP file photo

In this Aug. 12, 1993 file photo, U.S. President Bill Clinton points out people in the crowd to Pope John Paul II as he arrives in Denver, Co. | AP file photo

In this May 27, 1989, file photo, President George H.W. Bush gestures while standing with Pope John Paul II in the papal library at the Vatican. | AP file photo

Pope John Paul II walks with President Ronald Reagan in the garden of the Vizcaya, a lavish mansion on Biscayne Bay in Miami. | AP file photo

In this Oct. 6, 1979, file photo, President Jimmy Carter talks with Pope John Paul II at the White House | AP file photo

President Jimmy Carter smiles as he greets Pope John Paul II at the White House on Oct. 6, 1979. | AP file photo

In this Sept. 28, 1970, file photo, President Richard Nixon talks with Pope Paul VI as they meet in the Vatican. | AP file photo

Pope Paul VI and President Gerald Ford look over gifts they exchanged at the Vatican. | AP file photo

In this Oct. 4, 1965, photo, Pope Paul VI and President Lyndon B. Johnson are seen during the Pontiff’s visit to New York. | AP Photo

In this July 2, 1963 file photo, President John F. Kennedy and Pope Paul VI talk at the Vatican. | AP file photo

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