Pope Francis has suggested he would be open to studying whether the Catholic Church should ordain men who are married as priests to help deal with the shortage of clergy in remote areas of the world.

In an interview with the German newspaper Die Zeit published on Thursday, Francis said the church will maintain its standard of celibacy for most priests throughout the world, but it could study the idea of allowing “viri probati” — married men of proven faith — to be ordained.

If the idea were studied and approved by the Catholic Church, it would be an extension of a provision the church already has to accommodate married priests in exceptional cases. Priests in the eastern rite Catholic Church are allowed to be married, and during his short tenure Pope Emeritus Benedict XVI began allowing married Anglican priests who have converted to Catholicism to serve.

Francis has said in the past that priests should be celibate, but the rule was not dogma, and “the door is always open” to change. His latest interview suggested a particular case in which the church could consider ordaining married priests, such as clergy in remote locations.

It’s unclear whether the idea — if approved — would extend to the United States, and it’s likely a question bishops would propose to the pope if they saw the need, said Massimo Faggioli, a church historian at Villanova University. This is part of Francis’s vision of a decentralized church, he said, and the idea of celibate priests is more institutional, financial and cultural than it is theological.

The Catholic Church had married priests in its earlier years, though celibacy became a standard in the church and a flash point in the larger debates in the Protestant Reformation. In the United States, the celibacy requirement is partly what sets priests apart from clergy in Protestant denominations.

“Some people feel the need to make the Catholic Church have more visible boundaries,” Faggioli said. “If you dismantle [the celibate priesthood], people will say, what’s the difference between us and Episcopalian, us and Lutherans?”

The number of priests in the U.S. church has been steadily on the decline since the 1960s. In 2016, there were about 37,000 priests, compared to 58,000 in 1965, according to Georgetown’s Center for Applied Research in the Apostolate.

Brazilian Cardinal Claudio Hummes, a longtime friend of Francis, has been urging the church to allow married priests in the Amazon, where the church has about one priest for every 10,000 Catholics, according to the Associated Press.

The pope’s comment gives the impression that he’s not talking about Western Europe, where there is less of a clergy shortage, said Monsignor Stephen Rossetti, a Catholic University of America professor who has written books on psychological care for priests.

“He’s not saying we’re doing it, but he’s saying let’s run it up the flagpole and see what people think,” Rossetti said. “He’s saying he’s willing to make exceptions as a merciful gesture.”

In November, the pope made a surprise visit to the outskirts of Rome to meet several men who left the priesthood to get married.

Mathew Schmalz, a professor of religion at College of the Holy Cross, said that if a married Catholic man like him could become a priest, he’d be interested.

“I would certainly give it serious consideration,” he said. He thinks the option would be appealing to many of the Catholic Church’s married deacons and to other faithful Catholics, especially older men who have the time to devote to entering the priesthood. “I think initially there would be a great rush to become a priest.”

But Schmalz thinks that the idea might be less appealing to some in the pews. Celibacy, he said, suggests to many Catholics that priests have nearly superhuman spiritual gifts, to resist the normal human drive toward sexual and romantic relationships.

“For some Catholics, this is like yet another example of things they have taken for granted about Catholicism that are now being reexamined,” Schmalz said. “People have always liked pointing to their priests as somehow special people.”

The comments come as the pope has said the church will continue to disallow gay priests and female priests. In December, the church’s Congregation for the Clergy, in a document approved by Francis, reaffirmed the church’s position that priests should be celibate. The Catholic Church teaches that celibacy allows a priest to dedicate himself to God and to service of the church, a tradition of the church rather than a doctrine of the church.

“This is not a slippery slope of ordaining other kinds of clergy,” said Patrick Hornbeck, chair of the theology department at Fordham University. “He’s talking about broadening an existing practice. I would caution against reading too much into it.”

Since he was made pontiff, Francis has made comments to journalists that have caused confusion in the press and in the church. After he created a committee to study women serving as deacons, he said women probably will never be priests. He also wrote a major document on family issues suggesting people who have divorced and remarried outside the church might be able to receive communion, but it has caused confusion over whether the church’s position on who can take communion has changed.