Madrid ? In a visit billed as a mini-showdown with Spain’s Socialist government, Pope Benedict XVI drove home the importance of the traditional family before hundreds of thousands of pilgrims Sunday, insisting that marriage must be between a man and woman.

During a 26-hour trip, the pope met with Socialist Prime Minister Jose Luis Rodriguez Zapatero, whose government has legalized gay marriage and introduced other liberal reforms that have irked the Vatican. Government officials described the talks as cordial and said no criticism was exchanged.

There was no comment from the Vatican.

At an open-air Mass before leaving for Rome, Benedict reiterated that the family was “founded on indissoluble marriage between a man and a woman.”

The Mass came at the end of a nine-day church gathering focusing on family issues. Benedict said the next family congress would be in Mexico City in 2009.