Cardinal Donald Wuerl, the leader of the Washington archdiocese’s 620,000 Catholics, said Thursday that Catholic values call on the United States not to deport people already living in our country.

But Wuerl expressed caution about the idea of churches acting as sanctuaries for those seeking to avoid deportation, as some congregations across the country have offered.

“When we use the word sanctuary, we have to be very careful that we’re not holding out false hope. We wouldn’t want to say, ‘Stay here, we’ll protect you,'” he said, explaining that he’s not sure churches can legally guarantee protection to people who might move into a church building, or that federal agents would necessarily respect the boundaries of a church as a place that they cannot enter.

“With separation of church and state, the church really does not have the right to say, ‘You come in this building and the law doesn’t apply to you.’ But we do want to say we’ll be a voice for you.”

Wuerl made the comments in a meeting with editors at The Washington Post, where he discussed issues of interest to the Archdiocese of Washington, one of the nation’s most prominent Catholic dioceses.

Catholics have been torn politically since the election of President Trump. A majority of Catholics voted for Trump, but bishops and leaders of Catholic nonprofit organizations have fiercely opposed some of Trump’s policies in the first weeks of his presidency, particularly Trump’s attempt to suspend refugee admissions to the United States. Pope Francis has repeatedly spoken about the virtue of welcoming refugees and has made thinly veiled references to those who would build walls, as Trump has proposed doing along the country’s southern border.