VATICAN CITY — Pope Benedict XVI has reaffirmed his opposition to embryonic stem cell research, saying it's morally wrong to destroy an embryo no matter how beneficial the resulting treatment is.

Benedict made the comments Saturday to participants of a Vatican conference on adult stem cells convened under an unusual new partnership between the Vatican's culture office and a small U.S. biotech firm, NeoStem Inc.

Church teaching holds that life begins at conception. As a result, the Vatican opposes embryonic stem cell research because embryos are destroyed in the process. It supports research using adult stem cells.

Benedict said: "The destruction of even one human life can never be justified in terms of the benefit that it might conceivably bring to another."