Okay, so he's definitely looking for someone to look out for him. It's good that he wants a little contact, but doesn't need to be contained in a tight ball. That's just an explosion waiting to happen. I have a few suggestions.
The first is to extend your arena so to speak. If there are any ground poles you regularly use when you're schooling, bring them out into an open area outside the confines of the arena. This gives him something familiar in an otherwise unfamiliar venue. Walk him over and around the poles with the goal of maintaining a relaxed horse. If he stays relaxed, move up to trot and even canter if he'd doing well. He needs to know that even though he's in a new area, you're still up there to guide him.
The next exercise can be done with or without familiar objects or ground poles. Walk him away from the familiar area 20 steps, at your choice, turn around and come back. Then go 40 steps, turn around and come back. 80 steps, etc. The goal of this game is to keep a steady pace. If he walks the first part at a snail's pace, he comes back that way. He is not allowed to rush home. Again, this shows him you're there to take care of him. If he's so nervous that we won't even walk away, try the next exercise, which is the drunken walk.
The drunken walk involves keeping the horse's attention and "forward" motion without force or feeling trapped. This one works well for horses who freeze in place and like to grow roots instead of move forward. The rules are, use only one rein at a time, no leg and sit square. Simply walk away from the barn in a zig zag pattern. Take up contact on one rein to lead the horse off to one direction, then drop that rein and switch to the other one. This is an insanely simple exercise that does wonders for keeping the horse focused on its rider rather than scanning for anything that wants to eat it.
The ultimate goal for any of these is to end with a calmer horse than you started with. Just take your time. He'll get there. Hopefully one of these will help your horse. Good luck.
You just have to see your distance...you don't have to like it.