Japan will add Mozambique, Malawi and Zambia to its list of nations subject to tighter entry rules from Sunday following the discovery of a new coronavirus variant in South Africa, Prime Minister Fumio Kishida said.

Kishida told reporters Saturday his government wants to make sure that "border control measures are firmly implemented," one day after it started requiring travelers who have recently been to Botswana, Eswatini, Lesotho, Namibia, South Africa or Zimbabwe to spend 10 days in a government-designated facility upon arrival.

During the 10 days, travelers from the designated countries must take a coronavirus test on the third, sixth and 10th day after their arrival.

The World Health Organization said Friday a new coronavirus strain detected in South Africa is a highly transmissible "variant of concern" and named it "Omicron."

The emergence of the B.1.1.529 variant, first reported to WHO from South Africa on Wednesday, has caused authorities worldwide to react with alarm, with many nations moving quickly to tighten travel restrictions.

Britain was among the first countries to suspend flights from southern African countries.

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