Looking for advice on public displays of affection. I'm a 23-year-old female, and my boyfriend is 25.

As noted in the title, my long-distance boyfriend enjoys public displays of affection, while I'm not comfortable with them. During his recent visit, he kissed me in public without asking for my consent. In the country we are in, public kissing is considered inappropriate, which makes me extremely anxious about the situation. I'm fairly certain that no one saw us and there were no cameras around, but I still want to address this. How can I communicate to him that I don't want him to do this again? I would really appreciate some advice.