I would approach this subject but not in a pushy way. There is a way to bring this up that just lets him know you want but that is only a discussion not a directive. It is okay to talk about this as a couple. You may not be happy waiting for him. You should let him know your feelings on this and your hopes for the future. Tell him you need this next step to feel that you are making progress. If he is committed to you he will be able to discuss this openly. A relationship is based on what you both want and need from each other. You should always be able to talk about anything.
I would say to him that you are concerned about where the relationship is going and would like to really decide on some things now together. Have him feel that you want to negotiate. If you avoid feeling like you are giving an ultimatum then it should be a subject like any other for discussion
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