'Twas the night before Christmas, all over the house, not a creature was stirring – except for Justin Bieber, who chose Christmas Eve to announce his "official" retirement on Twitter.Bieber chose the eve of the release of his movie, Believe, to annouce his withdrawal from the world of pop in a series of Tweets direct to fans.Just last week, Bieber had told a Los Angeles radio station he planned to quit. "After the new album, I'm actually retiring, man. I'm retiring," he told Power 106 on December 17. However, he then suggested that was not, in fact, the case. "I want to grow as an artist, and I'm taking a step out, I want my music to mature," he added.It has been a troubled 2013 for the teen star. Highpoints have included his writing in the guestbook at the Anne Frank Museum in Amsterdam: "Hopefully she would have been a Belieber"; his assertion that he had met the president of Mexico, denied by said president; his being caught urinating in a bucket and showing disrespect to former US president Bill Clinton; accusations of speeding in his neighbourhood; his abandonment of a pet Capuchin monkey in Germany; his tour bus being raided for drugs; and a visit to the UK that saw him scrapping with a paparazzo, collapsing on stage, and infuriating parents by beginning a show 90 minutes late.(theguardian.com)ANN.Az