Bonding with rabbits is difficult, as they are a main prey species for many, many animals, and are easily frightened, and definitely not hard-wired to trust big animals.
The best thing you can do is sit quietly nearby as it plays outside the cage (try reading a book or something) and NEVER speak in a high pitched voice to it, their ears are very sensitive.
Also, when reaching out to pet it, try putting out your fingers, palm down, with your hand below his eye level (don't put your hands above and swoop down, it scares them) and slowly reaching towards it for a pat, let it sniff your fingers, speak quietly in a low voice, and if he hops away, just say "ok, (bunny's name), maybe later" QUIETLY, and wait for him to come by again. Never get impatient or make sudden movements. Never be loud or laugh suddenly either, if you can help it. They are very skittish, the trick is not to forget what you're doing when gentling a rabbit, and remain calm.
The best thing for you to do is be patient, slow, and quiet, sitting near, offering small tasty treats in your hand and being gentle. It may take awhile, but if you do this daily, for an hour a day, he will come to trust you. (as much as any bunny can trust a meat eater)
Hope this helps, let me know how it goes!!!