Chinese President Xi Jinping has proposed using a global QR code system to enable cross-border movement of people amid the coronavirus pandemic.

Addressing the virtual G20 summit on Saturday night, Xi said a global mechanism involving mutual recognition of health certificates, including nucleic acid test results in the form of QR codes, could be used to enable cross-border travel.

“We hope more countries will join this mechanism,” Xi said, according to a transcript published by state news agency Xinhua.

“We need to further standardise policies and establish fast tracks to facilitate the orderly flow of people.”

The proposal is part of China’s suggestions on what should be done to cope with the pandemic. Xi also repeated that China was willing to share its vaccines with the rest of the world.

QR codes are barcodes that hold information that can be scanned and read by smartphones. They are in widespread use in China but it is not clear whether other countries could or would sign up for such a system as a way of testing and tracking people.

Countries have different quarantine and entry rules for foreign passengers, making it hard for cross-border travel. Some are talking about opening up “travel bubbles” to make movement easier.

However, travel bubbles can be fragile – Hong Kong had to suspend its plan for one with Singapore for two weeks on Saturday, a day before it was expected to take effect, as a fourth wave of infections hit the city.

China has largely brought the coronavirus under control and has few domestic travel restrictions. But mobile phone QR codes to prove health status and travel records have been mandatory since February. A green QR code means the holder is healthy and can travel, while a yellow or red code means the individual has to be quarantined.

The Hong Kong government is reportedly preparing to roll out a QR code system to pave the way for Hong Kong residents to enter the mainland without a 14-day mandatory quarantine. A nucleic acid test might be required for the proposed code, and with a negative test result, an applicant could apply for a QR health code in an online system. However, such a health code has raised concerns among some about possible leaks of critical personal information.

For now, mainland China has a strict entry screening and quarantine system.

Starting from this month, China has significantly tightened its entry requirements by adding a Covid-19 IgM antibody test.

Most, if not all, foreign and Chinese nationals flying into the country are required to present negative results for both nucleic acid and IgM antibody tests administered 48 hours before boarding.

The two tests are also required for transit flights, effectively ruling out transfer flights to the country because no international airport can offer such services to passengers.

Previously, China-bound passengers were only required to show a negative result for a nucleic acid test taken 72 hours before boarding, as well as submit to 14 days of quarantine upon arrival.