Sky's thought of projection is interesting to me too because I was thinking since you don't trust him yet hugging, you've decided it's not you but him, with the problem of not believing you. Instead of getting into the whole hugging issue with him, afraid you'll lose him, you've just switched the problem so you have control again. How can he "prove" he believes you if you have already decided anything he says would be to protect himself and that he won't tell you the truth?

Were I you, I'd tell him he can't hug you "anyway" until he discusses/explains how he feels his hugging you will get you to trust him, what he means by that and how it will work. To me, that the whole tension thing surrounding the hug sounds like a "will struggle" he has walked you into and I wouldn't trust just out of sheer refusal to be "wrong"/give in. He's going to "make" you trust him with his hugs and you're going to "refuse" to let him believe you.