Pope has decreed that the Catholic Church cannot bless same-sex unions because God "cannot bless sin".The Vatican's orthodoxy office, the Congregation for the Doctrine of the Faith, issued a formal response to a question about whether Catholic clergy can bless gay unions.The answer, contained in a two-page explanation published in seven languages and approved by Pope Francis, was "negative".The decree distinguished between the church's welcoming and blessing of gay people, which it upheld, but not their unions since any such sacramental recognition could be confused with marriage.Did you know you can keep up to date with the latest news by signing up to our daily newsletter?We send a morning and lunchtime newsletter covering the latest.