Coronavirus cases have been rising in some parts of the country.
Airlines must turn back passengers who do not wear their mask "properly" despite repeated warnings, the Directorate General of Civil Aviation (DGCA) on Saturday said, asking them to ensure air travellers strictly follow COVID-19 safety rules.
A passenger should be treated as "unruly" and "If required, they may be dealt as per law" in case the person violates the protocols, the aviation regulator said.
The latest directives come amid rising coronavirus cases in certain parts of the country while domestic air traffic returns to pre-pandemic levels.
In a circular issued on Saturday, the DGCA asked airport operators as well to ensure that passengers wear their mask and maintain social distancing norms at all times during air travel.
The DGCA said it has been noticed that some travellers undertaking air journey do not follow COVID-19 protocols, which essentially involve wearing masks properly - not below the nose, right from entering the departing airport to exiting from the arriving airport.
Some passengers have been also been found not wearing their masks properly while onboard the aircraft, the regulator said.
"Onboard the aircraft, in case any passenger does not adhere to wearing a mask properly even after repeated warnings, he/she should be de-boarded, if need be, before departure," the circular said.
"In the case of any passenger onboard an aircraft refusing to wear a mask or violates the 'COVID-19 Protocol for passengers' even after repeated warnings, during the course of the flight, such passengers may be treated as 'Unruly' passengers," the DGCA said.
The circular said that the passengers will have to wear masks and maintain social distancing norms at all times during air travel, adding the mask shall not be moved below the nose except under exceptional circumstances.
The chief airport security officer and other supervising officers must personally ensure the rules are followed, it said, directing the Central Industrial Security Force (CISF) and police personnel posted at the entrance of the airport to ensure that no one is allowed to enter the airport without wearing a mask.
Any passenger found violating COVID-19 protocols at the airport should be handed over to security agencies after proper warnings, the directive said.
(With inputs from PTI)