Iran has imposed a 15-day ban on travelers from the U.K., France, Norway and Denmark as part of its efforts to curb further spread of the Omicron COVID-19 variant.

The ban was announced on state television on Sunday, as the country ramps up surveillance against the virus.

Iran is the hardest-hit country by the pandemic in the Middle East, having recorded 6,184,762 infections with 131,400 fatalities.

The country is banking on vaccinations to contain the pandemic, and has already fully vaccinated about 51.3 million of its 85 million people.

(With input from agencies)