Is a belief in rebirth a necessity for Buddhist practice?

Can someone be a wholehearted Buddhist practitioner if they entirely reject rebirth? Or is anyone that follows the Buddhist path while not subscribing to rebirth only getting half the story? Or is the non-rebirth believer deluding themselves if they follow the Dharma under that circumstance? Is the principle of rebirth lacking emphasis in some traditions perhaps? Or is it perhaps something that was culturally prevalent at the time of the Buddha but now can be safely disregarded? Or is it central to the enlightenment experience? Certainly the Buddha reports seeing clearly all his past lives on the occasion of his enlightenment. So in short is a belief in rebirth a necessity for Buddhist practice?