The Notebook hunk first found fame in the '90s when he was cast in the Disney variety show alongside Spears, and he admits they flirted with romance playing spin the bottle.
He says, "Britney was a sweetheart. She lived right above me, the girl next door. The little girl I used to play basketball and spin the bottle with."
But the actor insists he has lost touch with his old pal: "I mean, sometimes you are at the same event, but it's a lot like I imagine what it's like to run into someone from elementary school."
However, he's proud the Toxic hitmaker has found lasting success, like fellow Mickey Mouse Club co-stars Christina Aguilera and Justin Timberlake.
He adds, "It is remarkable, but it isn't, in a way. Now you have (singing contest) The X Factor and all that stuff, but back then it wasn't around. You give these kids an unparalleled work ethic, which is why you see the difference between 'N Sync and those other bands, and between Britney and Christina and the other girls."