VATICAN CITY —  Pope Benedict XVI on Friday reaffirmed his opposition to gay unions and condemned the trafficking of women and children.

The pontiff said traditional marriage is an irreplacable good for the entire society and called the union between man and woman the "natural cradle" of life.

He told representatives of Catholic family organizations in Europe on Friday that traditional marriage should not be confused with other forms of union.

Several European countries have approved same-sex unions, and California's Supreme Court on Thursday declared that gay couples can marry. Massachusetts is the only U.S. state to legalize gay marriage.

In meeting with bishops from Thailand on Friday, he strongly condemned the trafficking of women and children, calling it a terrible exploitation of human beings.

Thailand is a magnet for people from poorer neighboring Asian countries who take menial and dangerous jobs shunned by Thais.

In the meeting with the bishops, the pope praised efforts by the Catholic Church in Thailand to alleviate poverty. He said poverty is an underlying factor in human trafficking and prostitution.

He also criticized the entertainment and media industries for what he called the trivialization of sex.