Start with a very positive greeting and then disclose it. You'll have them onside straight away. I find that starting with a very upbeat "hi how are you?" or similar greeting in any situation takes people by surprise and gives them a much more positive view of you from the start. Just show then that Yeah you stutter but you are OK with it and they should be too. I have what I would say is moderate stutter and I've never missed a job that I've interviewed for. It works for all situations though if you start with friendly positivity rather then nervousness even if it's fake people respond to it.