Arrivals from Ireland will be exempt from the new UK travel rules that come into force from 4am on Tuesday, 30 November.
All other arrivals must take a PCR test before the end of day two and self-isolate until they have negative result.
“If your PCR test results are delayed, you must self-isolate until your test result is known or until day 14 after arrival, whichever is sooner,” says the updated text on the UK’s Department for Transport’s website.
The move comes after 10 countries in southern Africa were put on the UK’s red list due to concerns over the new Omicron variant of Covid-19, which was initially detected in South Africa.
Meanwhile, NPHET is meeting today, 29 November, to consider the Irish response to the threat of the new variant, but sources so far indicate that the Government will not rush to re-introduce the PCR requirement for international arrivals and will instead monitor the situation closely.