The Archbishop of Philadelphia has criticised Republican presidential front-runner Donald Trump, saying his call to end automatic citizenship for children born to illegal immigrants "plays on our worst fears and resentments". "Some in public life — notably, but not only, Donald Trump — have called for an end to birthright citizenship," Archbishop Charles Chaput said at a panel discussion on immigration at the Archdiocesan Pastoral Center. "This is a profoundly bad idea." The archbishop said he hoped immigration would be a key part of the discussions during the Vatican-sponsored World Meeting of Families in Philadelphia and the Pope's appearance during the closing weekend. The Pope has decried what he has called the "inhuman" conditions facing migrants crossing the US-Mexico border, and encouraged border communities not to judge people by stereotypes but rather welcome migrants and work to end discrimination. Without at first mentioning Trump by name, Archbishop Chaput began his remarks by declaring: "At least one of our presidential candidates has already made the national immigration debate ugly with a great deal of belligerent bombast." Trump has proposed the mass deportation of millions of immigrants living in the US illegally, as well as their American-born children. He also supports building a wall along the border. Archbishop Chaput, whose archdiocese has about 1.4 million parishioners, urged Congress to give those living in the US illegally "an honest, attainable chance at citizenship". He also said the nation should stop detaining young mothers with children who are fleeing violence in Central America. "These families pose no threat to anyone," he said. "Detaining them is inhumane." Of Trump's call to end birthright citizenship, he said: "It plays on our worst fears and resentments. And it undermines one of the pillars of the American founding and national identity."