Ireland is to apply an 'emergency brake' system to several countries, in response to a new variant of COVID-19.
The Omicron variant was first detected in South Africa, and has since been found in a number of other African states.
This includes Botswana, Eswatini, Lesotho, Mozambique, Namibia and Zimbabwe.
The first case in Europe was also confirmed earlier in Belgium.
The Government says travel from these African countries "poses a risk". However it says Ireland currently has no direct flights from any of these countries.
But it says passengers arriving from overseas are required to have proof of COVID-19 vaccine or recovery status - or evidence of a 'not detected' PCR test ahead of departure.
It adds that a number of further steps are now being taken.
Ireland is aligning with the EU recommendation to apply the 'emergency brake' in respect of the countries concerned.
This means member states should adopt an urgent, temporary restriction on all travel into the bloc from these areas.
But the emergency brake should not apply to EU citizens, long-term EU residents and certain categories of essential travellers.
While the Department of Justice is updating visa requirements for those countries, and the Department of Foreign Affairs has changed its travel advisory to 'avoid non-essential travel'.
Irish residents returning home from these countries will be required to undergo "strict home quarantine" - regardless of any vaccine/recovery/test status - and also undergo PCR testing during quarantine.
In a statement, the Government says Mandatory Hotel Quarantine options "are being examined on a contingency basis".
While Health Minister Stephen Donnelly says it will legislate to re-introduce the measure if needed to deal with the new variant.
And the Department of Transport says it has "engaged with carriers to ensure that all relevant pre-departure requirements... are rigorously complied with."