Speaking on Monday at a Vatican conference in Mexico City, Pope Francis said that thousands of unaccompanied child migrants should "be welcomed and protected" when they come to the U.S., according to Time.

Undocumented immigrants recently have grabbed political headlines in the U.S., as they continue to spill over the country's border with Mexico, mostly coming from other Central American countries.

U.S. law requires that the immigrants are processed and detained before being sent back to their home countries. The sheer number of those illegally crossing the border has created a backlog in deportations.

"They are increasing day by day," the Pope said. "The humanitarian emergency requires, as a first urgent measure, these children be welcomed and protected."

The Pope's request was not directed solely at the U.S., but at the international community, as he implored that countries work to inform migrants of the dangers of their journey and to improve economic development in those countries from which the immigrants are coming.

News reports estimates that, since October, around 57,000 children have come into the U.S. without documents.

"Given these migratory facts, we urgently need to overcome primitive misgivings and again propose common strategies at the sub-regional, regional and world levels that include all sectors of society," Vatican Secretary of State Cardinal Pietro Parolin said, according to the Catholic Herald.

"Whether they travel of reasons of poverty, violence or the hope of uniting with families on the other side of the border, it is urgent to protect and assist them because their frailty is greater and they're defenseless, they're at the mercy of any abuse of misfortune."

The Vatican's comments on the issue come just as the U.S. has started deporting many of the undocumented immigrants that have come into the country recently. On Monday, the U.S. deported 40 Hondurans that have been detained in the country, and more deportations are expected.