The Cabinet has agreed that people arriving in Ireland will need negative Covid test from Friday.
Travellers can have either a professional antigen test taken a maximum of 48 hours prior to arrival or a PCR test taken up to 72 hours earlier.
Proof of either test will be requested in Irish airports.
The new travel policy comes amid fears of the potential impact of the Omicron variant of the virus.
On Monday, the Department of Health said there are 11 suspected cases of Omicron in Ireland, which have been sent for whole genome sequencing.
4,607 cases of Covid-19 were confirmed in Ireland on Monday evening.