The Philippines will bar the entry of travelers from Japan and 19 other countries and territories, the transport ministry said Tuesday, as the Southeast Asian nation tries to keep out a new, possibly more transmissible variant of the coronavirus.

The ministry said the ban will be effective from Wednesday until Jan. 15 and applies only to foreign nationals who wish to travel to the Philippines. Returning Philippine citizens will be allowed back into the country but must quarantine for 14 days.

Passengers wear face masks at the Ninoy Aquino International Airport on January 23, 2020 in Manila, Philippines. (Getty/Kyodo)

"Travelers from any other country that subsequently reports the presence of the new COVID-19 strain shall likewise be banned from entering the Philippines," the country's Transportation Department said in an advisory.

Health experts worldwide have reported that the virus that causes the COVID-19 disease has already mutated into a possibly much more contagious variant.

Philippine health authorities say that the new strain has not yet been detected in the country.

Aside from Japan, the others included in the travel ban are Australia, Canada, Denmark, France, Germany, Hong Kong, Iceland, Ireland, Israel, Italy, Lebanon, the Netherlands, Singapore, South Africa, South Korea, Spain, Sweden and Switzerland.

Britain has already been under a travel ban since Dec. 24, which was due to expire at the end of the month, but the date has been extended to Jan. 15, in line with the new measures.

The ministry said travelers who are already in transit and arrive before the new restrictions start will be allowed entry into the country but must submit to PCR testing and a mandatory 14-day quarantine period.