Retired Pope to be removed as celibacy book author Published duration 14 January

image copyright Reuters image caption Pope Benedict stepped down in 2013 as he grew increasingly frail

The cardinal who co-wrote a book backing priestly celibacy with the retired Pope has said Benedict XVI's name will be removed from future editions.

Some saw the apparent intervention by Benedict as a challenge to his successor, Pope Francis.

Pope Benedict, who is 92, reportedly said he could not remain silent.

Francis is considering whether to relax the rules for married men in the Amazon region.

Cardinal Robert Sarah tweeted (in French) that in light of the controversy the publication had provoked, it had been decided that in future the named author would be himself alone, with the contribution of Benedict XVI noted. The text would remain completely unchanged, he said.

Pope Benedict's private secretary said he had asked Cardinal Sarah to request the changes.

The cardinal rejected accusations that he had taken advantage of the frail former pontiff, saying that Benedict knew that the project would take the form of a book.

Pope Benedict still lives within the walls of the Vatican in a former monastery.

But since then, he has made his views known in articles, books and interviews, advocating a different approach to Pope Francis, who is seen as more progressive.

What is the proposed change?

In October, Catholic bishops from around the world gathered for a meeting, known as the synod, to discuss the future of the Church in the Amazon.

At the conclusion of that meeting, a document detailing issues affecting the Church was released. In it, there was a suggestion that in remote parts of the Amazon, older, married men should be ordained.

South American bishops have advocated this in an effort to address the shortage of priests in the region.

image copyright Reuters image caption Pope Francis is seen as being less of a traditionalist than his predecessor

Pope Francis will consider it, along with many other proposals, including the environment and the role of women in the Church. He is expected to make a decision on the matter within the next few months.

There are already some exceptions, such as priests in Eastern Catholic Churches and Anglican priests who convert.

Why is it controversial?

Priestly celibacy was introduced about 900 years ago, and before then clergy were often married.

It is not explicitly required by the Bible but is a discipline required by the Church.

For many, celibacy is a key part of being a Catholic priest, one who is supposed to devote himself to the Church and not be distracted by what some consider to be worldly concerns like a wife or a family.

For traditionalists, this is about the direction in which Pope Francis is taking the Church.

Some critics regard the idea of allowing married priests in the Amazon as a pretext to abolishing celibacy as a requirement altogether.