The so-called Indian variant of COVID-19 in Britain is now the biggest threat to international travel for Ireland.
That is according to independent TD for Clare Michael McNamara.
It comes as the future of mandatory hotel quarantine is being debated by TDs in the Dáil.
Deputy McNamara told Newstalk Breakfast it it time for the system to go.
"I was never in favour of it - and I suppose now it seems the biggest threat comes from the United Kingdom, with the rise of the Indian variant there.
"And given we don't have the capability to introduce mandatory hotel quarantine in respect to people coming from the United Kingdom, which we have an open border with, I think that's the crux of the matter.
"And if we don't do that, then how do we justify the fact that we did make EU nationals - who in theory enjoy freedom of movement within the European Union, which includes Ireland - why did we make them go into mandatory hotel quarantine?
"That's something that we may well have to justify before the European courts at some time in the future."
He also said it was important to respect freedom of EU movement, rather than with the UK.
"The argument I'm making is that we should respect freedom of movement within the European Union, rather than a country which is outside of it.
"We shouldn't be adopting tokenistic measures that are costing huge amounts of jobs across our economy.
"If we were able to prevent variants coming into the country... but I don't believe that we can do that".
'International travel is the biggest threat'
Aoife McLysaght, professor of genetics at Trinity College Dublin, said now is not the time to scrap mandatory hotel quarantine.
"It's not the time - we have a quite volatile situation internationally.
"We've been talking for a long time how people would like to have the possibility of a summer in Ireland, where they can take a holiday in Ireland and enjoy some hospitality and all of those kind of things.
"And international travel is the biggest threat to that.
"So far the mandatory hotel quarantine has been actually reasonable effective in the sense that we were very worried about P1 variant, first identified in Brazil, and we've managed to contain that.
"And that's a success that has to be lauded."
Prof McLysaght said other variants will keep on emerging.
"There are other variants - yes the B1617.2 that's now in the UK, and other ones around - they're going to keep coming as the international situation is so volatile.
"So what we can do is manage our own internal situation, and that's what we should be doing".
And she added that Ireland's open border with the UK could present problems for travellers.
"There are countries in the EU that are talking about banning travel from the UK because of that variant.
"We could see ourselves on the wrong side of this equation if we let things go like that - that [countries] won't let Irish people, or people travel from Ireland, into their countries".