The former two-time world champion is expected to move up to welterweight to face the American, but he has already set his eyes on a potential encounter with Mayweather.
The 26-year-old told iFilm London: "If I win my next fight, it's the Floyd Mayweather fight. I've been guaranteed that.
"I've got one more obstacle to pass against Alexander and I'll get the Mayweather fight."
Khan overcame Julio Diaz on points in April.