The U.S. border czar has pushed back against Pope Francis' criticism of the U.S. mass deportation of migrants plan.

Francis took the remarkable step of addressing the U.S. migrant crackdown in a letter to the bishops of the United States, who have criticized the expulsions as harming the most vulnerable. History's first Latin American pope has long made caring for migrants a priority of his pontificate,

In the letter, the pope said the criminalization of migrants and the mass deportations planned by the U.S. government are dangerous and called the country's current immigration policies a “major crisis.

Pope Francis condemned President Donald Trump's administration for its deportation policies after the Vatican City State cracked down on its own borders. Francis, the first Latin American pontiff rebuked Trump in a letter criticizing mass deportations this week,