Mexico City federal prosecutors say they'll work to overturn the city's new gay marriage law.

The law, which was approved by the city's lawmakers on Dec. 21, legalizes same-sex marriage. It also allows gay couples to adopt children. It's the first law of its kind in Latin America.

Mexico's attorney general said Wednesday that the new law strays from the constitutional principle of protecting the family.

Meanwhile, the issue is dividing the strongly Catholic city, with one pro-family group calling gay marriage "total depravity."