Advances in Artificial Intelligence (AI) promise help for democratic deliberation, such as processing information, moderating discussion, and fact-checking. But public views of AI's role remain underexplored. Given widespread skepticism, integrating AI into deliberative formats may lower trust and willingness to participate. We report a preregistered within-subjects survey experiment with a representative German sample (n = 1850) testing how information about AI-facilitated deliberation affects willingness to participate and expected quality. Respondents were randomly assigned to descriptions of identical deliberative tasks facilitated by either AI or humans, enabling causal identification of information effects. Results show a clear AI penalty: participants were less willing to engage in AI-facilitated deliberation and anticipated lower deliberative quality than for human-facilitated formats. The penalty shrank among respondents who perceived greater societal benefits of AI or tended to anthropomorphize it, but grew with higher assessments of AI risk. These findings indicate that AI-facilitated deliberation currently faces substantial public skepticism and may create a new “deliberative divide.” Unlike traditional participation gaps linked to education or demographics, this divide reflects attitudes toward AI. Efforts to realize AI's affordances should directly address these perceptions to offset the penalty and avoid discouraging participation or exacerbating participatory inequalities.