China mandated the widespread use of QR-based health certificates earlier this year. The system, which uses an electronic barcode to store a person's travel and health history, has been credited with helping to curb the spread of the virus. The code issues users with a color code based on their potential exposure to the novel coronavirus. The colors are like traffic lights -- green is safest, then amber and finally red.
Speaking at the virtual G20 leaders' meeting on Saturday, Xi said that to ensure the "smooth functioning" of the world economy during the pandemic, countries needed to coordinate a uniform set of policies and standards, according to state-run news agency Xinhua.