The pope said he would travel to Philadelphia for the "World Meeting of Families," a Church-sponsored gathering that takes place once every three years.
Vatican sources said the trip, whose details have yet to be finalised, would also include an address to the United Nations and a stop at the Mexico border, though it was yet unclear in which state -- California, Arizona, New Mexico or Texas.
The organisers of the congress in Philadelphia said in a statement posted on the meeting's website that the pope was expected to visit the city from September 25-27 for the closing days of the meeting.