This guy keeps touching me in drama class and I hate it.?

So this guy, lets call him "A" he keeps touching me in drama class and I absolutely hate it to death. It's drama so it's okay to act with boys on stage and okay to touch /hug BUT he does that during the class time.

He randomly comes up to me and Hugs me. It disgusts me Like our teacher choses our groups and we mostly get in the same group.

Once we were doing a sceane where I was the bride and he was the groom. It was mime so we couldn't talk. On the stage, he touched my hair (it was not in our groups planning). When we finished rehearsing he would just comes up to me a d huges and me I hate it so I pushed him back. He would stand so close to me ugh.

Honestly, I don't mind doing it on the stage because its part of our marks but that guy does that too much and even when we as not rehearsing. It happened a lot of times.

I have told him a lot times to stop and pushed him away but he wouldn't stop. I told him I wi tell the teacher.

I have a male teacher so I am kind of shy to talk to him about this BUT I will! What do I do? How do I talk to the teacher?