SEOUL, May 26 (Xinhua) -- South Korea began the so-called "no mask, no ride" policy on buses and taxes on Tuesday to help prevent the spread of the COVID-19 while using public transportation.

Beginning Tuesday, taxi and bus drivers will be allowed to limit or refuse the ride of passengers who do not wear face masks. Drivers will be required to put on masks when passengers are on board.

Amid emerging worry about the COVID-19 infection while using public transportation, the health authorities allowed drivers to temporarily refuse passengers without masks.

As of Sunday, nine bus drivers and 12 tax drivers had been confirmed positive for the COVID-19.

By law, public transit drivers of bus, taxi and railway are banned from refusing passengers without proper reasons.

As the local law provides no legal grounds, the authorities cannot take administrative penalty on passengers without masks, so the authorities eased rules to allow drivers to refuse the passengers.

Meanwhile, subway passengers will be strongly advised to wear face masks while on board beginning on Tuesday.

The subway staff will encourage passengers to put on masks directly or via the subway announcement as it is not possible for check all the passengers.

From Wednesday, all passengers on domestic and international flights will be required to wear masks while aboard. Some of the domestic airlines have forced passengers to put on masks.