Chinese President Xi Jinping has made use of his authoritarian power in China to impose the world’s strictest controls against COVID-19. But there’s one pandemic measure he hasn’t pushed: vaccines.

China’s first attempt at a vaccine mandate was abruptly scrapped last week within days of it being announced by municipal officials in Beijing. The plan to stop people entering public venues without proof of vaccination sparked an outcry online, with Chinese social media users calling it an illegal cap on their freedoms and questioning how effective the vaccines are against immune-evasive variants.

Vaccine mandates have emerged as a surprise red line for the ruling Communist Party, which up until a few years ago controlled citizens’ reproductive rights through its one child-policy and is steaming ahead with other controversial virus curbs, such as widespread tracking of individuals through their phones, mass testing and border controls.