Catholics around the world could be urged to shun the Da Vinci Code prequel, which was banned from filming in the Holy See last summerThe Vatican looks likely to call for a boycott of Angels and Demons, the prequel to the blockbuster film adaptation of Dan Brown's The Da Vinci Code.Official Vatican newspaper Avvenire reported on Friday that it "cannot approve" of Ron Howard's film, which is based on the eponymous book by Brown and opens worldwide on 15 May.