Nigeria has been added to the UK travel red list as efforts to contain the spread of the Omicron variant of Covid-19 gather pace.

The change means UK and Irish citizens and residents arriving from Nigeria must isolate in a government-approved managed quarantine facility for ten days on arrival.

They must also receive two negative PCR tests, as further precautionary action is taken against the new variant.

Currently, the vast majority of cases in the UK have clear links to overseas travel from South Africa and Nigeria, and over the past week, 21 Omicron cases reported in England originate from Nigeria.

A temporary travel ban has also therefore been introduced for all non-UK and non-Irish citizens and residents who have been in Nigeria in the last ten days, meaning they will be refused entry into the UK.

This does not apply to those who have stayed airside and only transited through Nigeria while changing flights.

Last weekend, ten countries were added to the red list, and it was announced that all vaccinated passengers arriving in the UK must take a day two PCR tests and self-isolate until they receive a negative result.

Since then, the geographical spread of Omicron has increased considerably, with 37 countries around the world now reporting Omicron cases and over 134 cases identified in the UK.

Prime minister, Boris Johnson, has also confirmed pre-departure testing will also now be reintroduced.

New analysis conducted by the UK Health & Security Agency (UKHSA) indicates that the window between infection and infectiousness may be “shorter for the Omicron variant,” which increases the efficacy of pre-departure testing as it is more likely to identify positive cases before travel.

Analysis suggests there is strong indication of Omicron presence in Nigeria, and several cases identified in the UK are linked to travel from Nigeria.

The country also has very strong travel links with South Africa, for example Nigeria is the second most popular flight destination from Johannesburg.

The red list changes come into effect on Monday at 04:00.

Anyone touching down before this time is “strongly encouraged to isolate at home,” while their household should also self-isolate for ten days starting with their arrival in England, the government said.

Affected individuals will be contacted and offered free PCR tests to be taken on day eight after their arrival.