CAIRO — The concert seemed like it would be another adventurous step for ultraconservative Saudi Arabia: a pop star famous for lively love songs performing in a kingdom where, until recently, public concerts were prohibited.

But that was before the tickets went on sale, and buyers saw the terms and conditions.

“Dancing is strictly prohibited during the concert,” the tickets stated in fine print. Also banned: “Swaying.”

The regulations for the March 30 concert by Tamer Hosny, a popular Egyptian singer whose lyrics sometimes contain sexual innuendo, were issued by the kingdom’s entertainment authority and announced last Friday.

Greeted with criticism and mockery on social media in Saudi Arabia and elsewhere in the Middle East, the rules underlined the balancing act that the Saudi government must perform as it takes steps toward the liberalization called for by Crown Prince Mohammed bin Salman, in a society that may not be entirely comfortable with it.