Religious and social conservatives vowed Thursday to fight Gov. David Paterson's directive requiring state agencies to recognize gay marriages performed legally elsewhere, saying it flouts traditional values and is a big step toward legalizing same-sex unions in New York.

"The definition of marriage predates recorded history," said New York State Catholic Conference Executive Director Richard E. Barnes. "No single politician or court or legislature should attempt to redefine the very building block of our society in a way that alters its entire meaning and purpose."

Paterson issued a memo earlier this month saying that gay New Yorkers who marry where it is legal will have the right to share family health care plans, receive tax breaks by filing jointly, enjoy stronger adoption rights and inherit property.

He cited a February ruling in a New York Appellate Division court in which the judges determined that there is no legal impediment in New York to the recognition of a same-sex marriage.

Earlier this month, the California Supreme Court ruled that same-sex marriage in the nation's most populous state is legal. The ruling overturned a voter-approved ban on gay marriage.