A 48-hour ban on flights from Britain will start at midnight tonight, the Transport Minister has confirmed.
Eamon Ryan says ferry connections with Britain will be for cargo only.
Several other European countries - including the Netherlands, Italy and Belgium - have also banned flights from the UK amid concern over a new strain of coronavirus that has been detected in England.
Cabinet is expected to review the situation when it meets on Tuesday - with Minister Ryan saying the travel ban may be extended.
Meanwhile, the Northern Ireland Executive will meet this evening to discuss the issue.
Elsewhere, the Labour party has called for mandatory COVID-19 testing at ports in response to the latest developments.
The party's TD Duncan Smith urged the Government to bring forward the Cabinet meeting scheduled for Tuesday, and to 'ramp up' testing and tracing capacity over the coming days.
He said: “If this new strain is so widespread now in the UK then it is highly likely it could already have spread to Ireland but we don’t have testing at our frontiers to catch it.
“What this shows is the urgent need for mandatory COVID-19 testing at our airports and seaports for visitors arriving into Ireland over the coming days and weeks."