Royal Caribbean has introduced a new rule that all passengers must wear masks indoors due to the latest wave of coronavirus sweeping around the world.

All passengers, including those who are fully vaccinated, must cover their faces in all indoor public spaces unless eating and drinking.

Norwegian Cruise Line is also understood to have amended its policy to insist that masks are worn indoors.

Previously, Royal Caribbean allowed passengers to go maskless in areas reserved for those who were fully vaccinated, which included the spas, some speciality restaurants, some areas of the theatres and specific bars and lounges.

However, the cruise line has changed its policy to require all passengers to wear masks, at least on sailing departing up to 5 January.

It says its policy will be reviewed early in the new year.