The new rules mandates travellers to pre-book a COVID-19 test, which will be done on arrival.
The global health body said it was too early to say whether an Omicron-specific vaccine was needed to tackle the virus.
Lagos State maintained its lead on Nigeria’s COVID-19 table with 833 cases, down from 845 cases it recorded on Thursday.
The agency says Nigeria has now identified a further 39 cases of the omicron variant, bringing the total number of confirmed infections to 45.
“As of December 19, Nigeria reported 223,887 cases and 2,985 deaths in the 36 states and the Federal Capital Territory.”
This development follows the British government’s removal of Nigeria and the other African nations from its COVID-19 travel red list.
The UK reported 1,239 additional cases of Omicron on Sunday, bringing the total number to 3,137.
“Now that Omicron has been found in many non-African and developed countries, why are travels from those countries not banned? Why single out African countries?”
The decision was announced in a statement issued on Sunday by the British High Commission.
Adult travellers will be required to pay £2,285 (about N1.7 million at BDC rates) for 1 room for 10 days (11 nights), and an extra rate for 1 adult or child over the age of 11 is £1,430.
