Malta is set to have the strictest rules in the EU on mask-wearing outside, according to a Times of Malta analysis, with only one other country in the bloc requiring its citizens to mask up everywhere.
Health Minister Chris Fearne announced this week that from Saturday, everyone must wear a mask while outside, bringing back a restriction that last applied in the summer.
Cyprus is the only other EU member state with a similar rule - but even then, it allows people to go mask-free outdoors if they are alone or in pairs.
The health minister's announcement on Thursday has sparked public backlash, with people asking why masks are necessary for individuals in uncrowded spaces outdoors.
"So in a confined space in a restaurant, you can be without a mask, but if you're walking in an open space by yourself, you have to wear a mask? Who comes up with such idiocy?" wrote one commenter on social media.
Fearne has defended the measure, as a way to contain COVID-19 amid rising numbers and the expectation that Malta will record its first Omicron variant cases in the coming weeks.
How do Malta's rules compare with other EU member states?
On paper, Malta already had strict rules around masks. Currently, masks must be worn outdoors in groups of more than two people, if vaccinated, and even when alone if unvaccinated. But these rules have not been widely enforced.
The legal notice underpinning the new rules, and outlining any fines, has yet to be published.
In Cyprus, masks are mandatory outdoors for everyone aged over six and in groups of more than two people, according to a decree announced last month. Failure to comply results in a €300 fine.
In areas classified as yellow zones in Italy, mask-wearing is obligatory both indoors and outdoors at all times, however, at the time of writing, most of Italy remains a white zone, with only one region, Friuli Venezia Giulia, classified as a yellow zone.
The capital city of Rome has also put in place a temporary outdoor mask mandate until December 31 to reduce the risk of infections.
Spain, Portugal, Greece, Bulgaria, Finland, Latvia, Poland, Slovakia, Slovenia and the Czech Republic all require mask-wearing outdoors but only in crowded spaces.
Typically this means people are required to wear a mask if they can't mantain social distancing ranging from 1 to 1.5 metres from another person.
Many specify masks should be worn outdoors in crowded areas, such as markets, waiting outside buildings or during public demonstrations.
The remaining member states focus their mask rules on transport and enclosed public spaces.
Some countries, including Austria, Slovakia, Slovenia and the Czech Republic, specify that face-coverings should be FFP2 face masks.
What do health bodies say about outdoor mask use?
The World Health Organisation (WHO) recommends that each law-maker take a risk-based approach when considering mask use for the general public.
In areas of suspected community clusters or COVID-19 transmission, the WHO advises that people wear non-medical masks indoors or in outdoor settings where a physical distance of at least one metre cannot be maintained.
People should also consider wearing masks in crowded outdoor settings, such as open-air markets, lining up outside a building or during demonstrations.
Additionally, the WHO recommends that people with a higher risk for severe complication from COVID-19 should wear medical masks in any setting where physical distance cannot be maintained.
The US public health agency, the Centers for Disease Control (CDC), says that everyone over the age of two who is not vaccinated should wear a mask in indoor public spaces, but in general, it is not necessary to wear a mask in outdoor settings.
Similarly, the European Centre for Disease Prevention and Control (ECDC) recommends wearing a medical or non-medical face mask in confined public spaces and should also be considered in crowded outdoor settings.
The elderly and those with underlying medical conditions should consider using masks in any setting as a means of personal protection.