What does he see the relationship as?

You can't do anything to force a commitment, you can only give your love.

Maybe he really just doesn't want a committed relationship. He may have been hurt before or any of a million reasons. Even committing to being exclusive can a big step. If he's not ready, he's not ready.

You know better than any of us what your relationship is like. He may never commit. He may. Who knows? But if this is something that is extremely hurtful to you, you would have to let him know and possibly have to end the relationship.

But from what you posted, it seems like you feel it's a relationship that may go somewhere and it just may take time. Sometimes it's all about communication. You can talk, just be open and don't force it.