"We are going to ban all (new) entries of foreign nationals from around the world from November 30," Prime Minister Fumio Kishida told reporters.
Japanese returning from nine southern African states and countries where infections with the new variant have been identified will have to submit to "strict isolation measures based on risk," said Mr. Kishida.
Japan, which put in place border restrictions at the start of the pandemic, eased its measures for business travelers, students and foreign interns in early November, but remains closed to tourists.
The Japanese government announced on Friday the extension to ten days of the quarantine at the hotel for visitors from South Africa, Botswana, Eswatini, Lesotho, Namibia and Zimbabwe arriving on the ground Japanese.
Tokyo extended this measure this weekend for visitors arriving from Malawi, Mozambique and Zambia.
First identified in South Africa, the Omicron variant prompted many countries to close their borders to southern Africa when they had sometimes barely reopened to the world.
Beyond southern Africa, contaminations with this new strain have been detected across the G7 countries, from Canada to Italy, including Great Britain and Germany.
The appearance of the Omicron variant was deemed "worrying" by the World Health Organization (WHO), which however calls for maintaining open borders.
© 2021 AFP