Pope Francis says he believes the Roman Catholic Church's ban on women becoming priests will never be changed, in some of his most definitive remarks on the issue.
He was speaking aboard a plane, taking him back to Rome from Sweden, in a freewheeling news conference that has become a tradition of his return flights from trips abroad.
A Swedish reporter noted that the head of the Lutheran Church, who welcomed the Pope in Sweden, was a woman.
She then asked if he thought the Catholic Church could allow women to be ordained as ministers in the coming decades.
"St Pope John Paul II had the last clear word on this and it stands, this stands," Pope Francis said.
He was referring to a 1994 document by Pope John Paul that closed the door on a female priesthood.
The Vatican said this teaching was an infallible part of Catholic tradition.
The reporter then pressed the Pope, asking: "But forever, forever? Never, never?"
Francis responded: "If we read carefully the declaration by St John Paul II, it is going in that direction."
He has previously said that the door to women's ordination was closed, but proponents of a female priesthood were hoping that a future pope might overturn the decision, particularly because of the shortage of priests around the world.
The Catholic Church teaches that women cannot be ordained priests because Jesus willingly chose only men as his apostles.
Those calling for women priests said he was only following the norms of his time.