* Spokesman says pope not limiting use to gay prostitutes
* Says use by heterosexuals, transsexuals, also justified
* Clarification needed because of translation error in book
By Philip Pullella
VATICAN CITY, Nov 23 (Reuters) - Pope Benedict's landmark acknowledgement that the use of condoms is sometimes morally justifiable to stop AIDS is valid not only for gay male prostitutes but for heterosexuals and transsexsuals too, the Vatican said on Tuesday.
The clarification, the latest step in what is already seen as a significant shift in the Catholic Church policy, came at a news conference presenting the pope's new book: "Light of the World: The Pope, the Church, and the Sign of the Times".
In the book, a long interview with German Catholic journalist Peter Seewald, the pope used the example that a male prostitute would be justified using a condom to avoid transmitting the killer disease.
The clarification was necessary because the German, English and French versions of the book used the male article when referring to a prostitute but the Italian version used the female article.
Vatican spokesman Father Federico Lombardi said he asked the pope directly about it to clarify his thinking.
"I asked the pope personally if there was a serious distinction in the choice of male instead of female and he said 'no'," Lombardi said.
"That is, the point is it (the use of a condom) should be a first step towards responsibility in being aware of the risk of the life of the other person one has relations with," Lombardi said.
"If it is a man, a woman or a transsexual who does it, we are always at the same point, which is the first step in responsibly avoiding passing on a grave risk to the other.
CONDOMS ONCE CALLED "THE BIG LIE"
The church had been saying for decades that condoms were not even part of the solution to fighting AIDS, even though no formal policy on this existed in a Vatican document.
The late cardinal John O'Connor of New York famously branded the use of condoms to stop the spread of AIDS as "The Big Lie".
In the book, the pope says the use of condoms could be seen as "a first step towards moralisation", even though condoms are "not really the way to deal with the evil of HIV infection".
After the pope first mentions that the use of condoms could be justified in certain limited cases, the author, Seewald asks: "Are you saying, then, that the Catholic Church is actually not opposed in principle to the use of condoms?"
The pope answers: "It of course does not regard it as a real or moral solution, but, in this or that case, there can be nonetheless, in the intention of reducing the risk of infection, a first step in a movement toward a different way, a more human way, of living sexuality."
The pope's words and Lombardi's explanation -- while not changing the Catholic ban on contraception -- were nonetheless greeted as a breakthrough by liberal Catholics, AIDS activists and health officials.
"For the first time the use of condoms in special circumstances was endorsed by the Vatican and this is good news and good beginning for us," said Margaret Chan, director-general of the World Health Organisation.
While some Roman Catholic leaders and theologians have spoken about the limited use of condoms to stop the spread of HIV/AIDS as the lesser of two evils, this is the first time the pope has mentioned the possibility.
"It is a marvellous victory for common sense and reason, a major step forward towards recognising that condom use can play a vital role in reducing the future impact of the HIV pandemic," said Jon O'Brien, head of the U.S. group Catholics for Choice.
"This is a significant and positive step forward taken by the Vatican," said UNAIDS Executive Director Michel Sidibe. "This move recognizes that responsible sexual behaviour and the use of condoms have important roles in HIV prevention." (Writing by Philip Pullella; additional reporting by Tom Heneghan in Paris; editing by Ralph Boulton)
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