The 26-year-old singer was reflecting on the differences between himself and Harry, with whom he enjoyed massive global success as a member of British boyband One Direction, when he made the comparison.
Asked by The Face magazine which of his ex bandmates he'd most like to take a walk with, Liam replied: "To be honest with you, more than anyone, probably Harry. With Harry there's so much mystery around who he's become."
"I was looking at some pictures of him the other day, and I just thought, 'I don't know what more I'd say to him other than, 'Hello' and 'How are you?' I mean, look at the stuff I put out and the stuff Harry puts out. Polar opposite... I'm like the anti-Christ version of what Harry is."
When it comes to his other bandmates, Liam added that there's less mystery surrounding them.
"I speak to Louis (Tomlinson) quite regularly,” he smiled. "And I feel like I know where I stand with Niall (Horan)."