VATICAN CITY -- Pope Benedict XVI has praised the "great generosity" of American Catholics in welcoming new immigrants and backed the commitment of bishops in the United States to immigration reform.

Benedict on Friday held the last of a series of periodic meetings with American bishops over the past few months, saying the church must embrace "the rich patrimony of faith" from newly arrived Hispanic, Asian and African Catholics.

He acknowledged that immigration reform -- a hot button issue in the election campaign -- is a complex civil and political issue.

In his earlier meetings with the visiting U.S. bishops, Benedict has touched on other controversial issues that have featured in the presidential campaign, including condemning the gay marriage lobby and stressing the need for the Catholic Church to be free to pursue its religious teaching.