The Vatican has confirmed that Pope Francis will visit Portugal in 2017 to mark the 100th anniversary of the Marian apparitions of Fatima.

The Pope, who accepted the invitation made by President Marcelo Rebelo de Sousa and the bishops of Portugal, "will go on a pilgrimage to the Shrine of Our Lady of Fatima from May 12-13," the Vatican announced on December 17.

The pilgrimage will mark the anniversary of the Marian apparitions, which first began on May 13, 1917, when three shepherd children reported seeing the Virgin Mary.