The World Health Organization (WHO) has changed its advice on face masks, saying they should be worn in public to help stop the spread of coronavirus.
The global body said new information showed they could provide "a barrier for potentially infectious droplets".
Some countries around the world already recommend or mandate the wearing of face coverings in public.
The WHO had previously argued there was not enough evidence to say that healthy people should wear masks.
Over 60s with underlying health conditions should go further, the WHO said, and wear medical-grade masks to give themselves better protection.