The public could be advised against travel to Northern Ireland later this week amid the worsening Covid crisis there.
Tánaiste Leo Varadkar outlined the possible warning against going to the North at a meeting of Fine Gael TDs and senators last night.
He made the remarks as he discussed plans for the Government to ease Level 5 restrictions here from next week and move back to Level 3.
Mr Varadkar said it was unclear to what extent hospitality can be reopened and at what point people will be allowed to leave their county or whether they will be allowed to do so for longer than Christmas week.
Earlier, at the launch of the Look for Local Christmas shopping campaign he indicated that restrictions on meeting family and friends could be eased for around two weeks.
Under current Level 5 Covid restrictions people are not allowed visit each other's homes apart for essential reasons.
Last night he told the Fine Gael parliamentary party that there was an outstanding question over Northern Ireland and whether the Government would advise against any travel there.
Mr Varadkar cited the worsening situation with the spread of the disease in the North.
There have been nearly 2,500 Covid cases in the North in the last seven days, including 533 reported yesterday.
Mr Varadkar also said the Government will need to be frank with people that it is inevitable that with an easing of restrictions from next week more people will get the virus.
This may mean more people end up in hospital and more people potentially dying.
He said that this could mean restrictions may have to be reimposed for a shorter period than the current lockdown and that it would be possible for two weeks or three in January or February.
He said that while there were significant excess deaths in the first wave of the virus there were little or no excess deaths in the current second wave.
On the forthcoming vaccine, Mr Varadkar said he was now more confident than ever that 2021 will be the year the pandemic is going to be over and the economy bounces back.
He told TDs and senators that people in Ireland could be vaccinated in the first three months of next year.
The meeting heard calls from TDs for the reopening of pubs.
Minister Patrick O'Donovan and Clare TD Joe Carey were among those who argued these were more controlled environments and would reduce the number of house parties.
Mr Varadkar said he was confident people will be able to attend mass from next week but was said to be less optimistic about pubs reopening.
He launched the Look for Local campaign in Dublin's Docklands yesterday.
It is encouraging people to do their Christmas shopping with Irish retailers on their premises as restrictions are eased next week or online.
On families meeting up, he said: "We want people to be able to meet their families, meet their friends over the Christmas period. We know people are going to do it anyway so it's better that we provide for it in a safe way. Because we've got the virus down, much lower levels than in Northern Ireland or in Britain, we think we'll be able to do that for a much longer period than the five or six days they're talking about.
"We hope to be able to do it for something close to two weeks."
He said restrictions would be tightened again in January but added it will depend on the Covid-19 case numbers.
"If we're able to keep the numbers low we won't reimpose restrictions just for the sake of it," said Mr Varadkar. "We'll only reimpose restrictions if we think the virus is taking off again. We need to actually keep it under control to keep the numbers down at least until the vaccine is available."
The Tánaiste would not be drawn on suggestions that three households may be allowed meet up for Christmas dinner.
He said it would be Friday before such announcements would be made.
"Of course it's the Government's objective to allow people to have a family dinner on Christmas Day as normal as is possible but it's too early to make that call yet," he said.
He said gyms, shops and hairdressers can reopen next week.