Paternity Test: Why won't my baby's father to give me a paternity test for our 15 day old daughter?

He refuses to give me a paternity test but he has told people that she is not his. So when I suggested a paternity test he told me that he will never give me a test. Why won't he give me a test? But he wants to call and check on her! I asked him, why would you be concerned about a baby that you say isn't yours?