The Pope has backed abstinence over condoms
The Vatican is preparing to publish a statement on the use of condoms by people who have Aids, a senior Roman Catholic official has said.
Cardinal Javier Lozano Barragan told La Repubblica newspaper that Pope Benedict XVI asked the Vatican's council for health care to study the issue.
The Vatican says abstinence is the best way to tackle HIV/Aids.
But last week, a retired archbishop backed the use of condoms for married couples to prevent Aids transmission.
Cardinal Carlo Maria Martini, who used to be Archbishop of Milan, said that in couples where one partner had HIV/Aids, the use of condoms was "a lesser evil".
There are signs that the document could be a major revision of Vatican policy, says the BBC's Robert Pigott.
The issue is one of the most controversial among Catholics, and the Church has been strongly criticised for its current position, especially in African countries stricken by HIV/Aids, our correspondent says.
In his interview with the newspaper, Cardinal Barragan said: "Soon the Vatican will issue a document about the use of condoms by persons who have grave diseases, starting with Aids."
He said his department was studying the document, along with the scientists and theologians who wrote it.
"It is Benedict XVI who asked us for a study on this particular aspect of using a condom by those afflicted with Aids, and by those with infectious diseases," he added.
Asked whether he agreed with Cardinal Martini's views, Cardinal Barragan said: "It is a very difficult and delicate subject which warrants prudence."
He said he preferred not to comment on Cardinal Martini's remarks, so as "to not anticipate the study".
It is not clear when the document will be published.
The Vatican has made no official comment.