Mario Lopez claims Taylor Swift and Harry Styles were holding hands backstage at 'The X Factor'.'X Factor' host Mario Lopez was surprised to see the One Direction hunk on the set of the show this week, until he explained he was with the 'Begin Again' singer, who was this week's guest performer, and he claimed the pair seemed very close.Speaking on his 104.3 MY FM radio show, Mario said: "Taylor Swift was the special guest performer, and [here's] a little inside scoop for you."During rehearsals, Harry from One Direction came and slapped me on the back, and said, 'Hey, Mario, how ya doing?' And I said, 'What are you doing here?' And he sort of [pointed] toward Taylor."[Later I saw them] walking off hand in hand. So Taylor Swift and Harry from One Direction - you heard it here first. [They're] officially hanging out, I can say that much."And it seems that Harry, 18, is already getting on well with 22-year-old Taylor's family.A source told E! Online: "Harry is there with her now. She is doing rehearsals this afternoon...He was sitting with her mom and the rest of her entourage."After she finished, he went up to the stage. They were joking and laughing. He picked her up and threw her over his shoulder and carried her off."Taylor has been single since her recent split from Conor Kennedy, while Harry has been linked with a string of women, including singer-and-actress Natalie Imbruglia and model Cara Delevingne.