VATICAN CITY – Pope Benedict XVI is pressing his opposition to gay unions.

He says traditional marriage is an irreplaceable good for the entire society, and calls 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 said gay couples there can marry. Massachusetts is the only U.S. state to legalize gay marriage.