Fidelity in marriage and premarital abstinence from sex are the key weapons in the fight against AIDS, a senior Vatican cardinal, who prepared a study on condom use, said Wednesday. Cardinal Javier Lozano Barragan, who heads the Vatican office for health care, told the Associated Press that it was not yet known whether the Vatican would issue a document about the use of condoms after examining the study his office had prepared at the request of Pope Benedict XVI.

But, on the sidelines of a conference on AIDS sponsored by the U.S. Embassy to the Holy See, he said the request for the study ''shows the desire of the pope'' to battle AIDS and demonstrates that ''he is not indifferent to this difficult problem.'' The Vatican study on condoms deals only with married couples in which one partner has HIV.

In remarks to the conference, Barragan reiterated church teaching on how to prevent the spread of HIV, saying individuals must ''have the courage to proclaim clearly chastity'' in a society in which sex is part of the pursuit of pleasure.

The study on condoms was prepared with the help of scientists, theologians, and other experts exploring scientific, moral, and technical points of view. The Roman Catholic Church opposes the use of condoms as part of its overall teaching against contraception. It advocates sexual abstinence and sexual faithfulness between husband and wife as the best ways to combat the spread of HIV.

But several leading churchmen have spoken out on the issue in recent years as the Vatican has come under increasing criticism. Some, such as retired Milan cardinal Carlo Maria Martini, say condoms were the ''lesser evil'' in combating the spread of AIDS. Barragan, of Mexico, has said condoms could sometimes be condoned, such as when a woman cannot refuse her HIV-positive husband's sexual advances.

Other cardinals, however, have rejected the idea that condoms could be used, including Cardinal Alfonso Lopez Trujillo, who has contended that condoms may help spread AIDS through a false sense of security.

Karen Stanecki, a senior adviser to the Joint United Nations Programme on HIV/AIDS, told the conference that AIDS is on the rise among married women, including in Ghana, where married women were three times as likely as nonmarried women to be infected. ''There is a concern that the messages need to be changing,'' said Stanecki, referring to the long-standing warnings targeting higher-risk populations like sexually active gay men and intravenous-drug users.

She said U.N. officials were ''very pleased that Pope Benedict has been speaking more about AIDS in his speeches.'' (AP)