The Vatican heatedly defended Pope Benedict XVI, claiming accusations that he helped cover up the actions of paedophile priests are part of an anti-Catholic "hate" campaign targeting the pope for his opposition to abortion and same-sex marriage.

Vatican Radio broadcast comments by two senior cardinals explaining "the motive for these attacks" on the pope and the Vatican newspaper chipped in with spirited comments from another top cardinal.

"The pope defends life and the family, based on marriage between a man and a woman, in a world in which powerful lobbies would like to impose a completely different" agenda, Spanish Cardinal Julian Herranz, head of the disciplinary commission for Holy See officials, said on the radio.

Cardinal Herranz didn't identify the lobbies but "defence of life" is Vatican shorthand for anti-abortion efforts.

Also arguing that Benedict's promotion of conservative family models provoked the so-called attacks was the Vatican's dean of the College of Cardinals, Angelo Sodano.

"By now, it's a cultural contrast," Cardinal Sodano told the Vatican newspaper L'Osservatore Romano. "The pope embodies moral truths that aren't accepted, and so, the shortcomings and errors of priests are used as weapons against the church."

Also rallying to Benedict's side was Italian Cardinal Giovanni Lajolo, who heads the Vatican City State's governing apparatus.

The pope "has done all that he could have" against sex abuse by clergy of minors, Cardinal Lajolo said on Vatican radio, decrying what he described as a campaign of "hatred against the Catholic church".