I decide. He generally is silent until I speak. If he is pushing me in a direction I don't want to go, I can say "I don't want to talk about that now" and we move on to something I do want to talk about.
Bring it up with your T. Does your T talk first or do you. Try it out and not say anything for a minute when you first show up and see what happens. Your T may have counter-transference issues going on and may feel the need to "lead" you or the conversation.