The United Arab Emirates is the first country to rate a front-running Chinese vaccine for Covid-19, saying it was 86% effective in a phase-three trial.
The vaccine, produced by China National Pharmaceutical Group, or Sinopharm, has been officially registered, the UAE state news agency reports.
The health ministry said analysis shows no serious safety concerns.
However, neither Sinopharm nor the UAE have released detailed data on the trial of 31,000 participants.
The announcement did not say how many of those taking part had become ill or give numbers for those given the vaccine or a placebo.
There was also no information on side effects.