But the pope also reaffirmed the church's ban on artificial means of birth control and said Catholics should practice "responsible parenting."

His comments on the subject of birth control, made aboard the papal jet returning to Rome from the Philippines, were described as apparently unprecedented by the National Catholic Reporter, an independent news organization that follows the Vatican.

Francis said there are plenty of church-approved ways to regulate births. He also said no outside institution should impose its views on regulating family size, blasting what he called "ideological colonization" of the developing world.

African bishops have long complained that Western ideas about birth control and gay rights are being imposed on the developing world by groups, institutions or nations, often as a condition for development aid.