The Irish Government has been asked to restore the Aviva Stadium capacity to 100% by the weekend ahead of the Guinness Six Nations kick-off in early February.
Ireland are to face Wales at the Lansdowne Road venue on Saturday, February 5 but under current rules, crowds for sporting events are capped at 5,000 due to the wave of Covid-19 cases caused by the Omicron variant last month.
That ruling was put in place until January 31 - however the Minister for Health, Stephen Donnelly, has expressed optimism that the cap on spectators will soon be lifted as he now believes the Omicron peak has passed.
NPHET are due to meet with the Cabinet to discuss the situation further this week.
IRFU chiefs are hoping that they will get the green light to have full capacity crowds for the three home games in the championship, with Italy and Scotland following Wales to Dublin.
The tournament is fast approaching and Ireland boss Andy Farrell will name his Six Nations training squad tomorrow.
For Martin Murphy, the Aviva Stadium director who is also the chairman of the return of spectators working group that involves the FAI, GAA and IRFU, says a decision is needed by the weekend if full capacity can be achieved for the Six Nations opener.
"We've been working with the Department of Sport and Ministers Jack Chambers and Catherine Martin for the past two years, and made a lot of progress in that time culminating in full houses in November, which we ran safely," Murphy told RTE Radio.
"And we hoped our work was done at that stage but along came Omicron and that has put a spanner in the works.
"We've got Wales up first in the Guinness Six Nations and we've also got the National Leagues kicking off on the 29th of January.
"So we made representations to Minister Chambers yesterday and recommended that we revert to full houses.
"We quoted the situation in Wales and Scotland, where Wales were behind closed doors and Scotland had a capacity of 500, and they have both decided to go with full houses.
"France are due to make a decision this week so we're hopeful that we'll follow suit.
"Currently we're at 5,000 and that's due to be reviewed. Anything less than 100% is quite problematic in terms of mobilizing staff and the distribution of tickets, bearing in mind that a considerable number of Welsh supporters have already planned to come to Ireland, it's very difficult if we're not at 100%.
"We've been working on this for a number of months but we're really up against the wire and we would really need a decision this weekend in order to get things working smoothly."
Murphy added that there was a need for the Government to act quickly with the GAA's National Leagues ready to start on the final weekend of the month.
"Well, there is because the current regulations come up until the 30th of January and the National League matches are on the 29th and 30th, and also then there's the question of the 8pm curfew which affects some of those matches," he said.
"League of Ireland doesn't come into play until later in February and we'd hope that things will be much improved by then."
Earlier, Minister Donnelly revealed that a chance meeting with Johnny Sexton prompted a discussion about the possibility of crowds returning next month for matches.
“If advance warning could be given for people to plan, I think that would be fantastic, but I just don’t want to raise hopes in an unhelpful way,” Donnelly told RTE.
“I bumped into a hero of mine, Johnny Sexton, earlier this week. He, very understandably, said, ‘Can we get back to a full crowd at Lansdowne Road for the Wales game? As we did for the autumn internationals.’
“I can tell you there is nothing I would like more than to hear the roar of 50,000 people at the start of February.
“We have to get the balance right. We need to move forward, and put Omicron behind us, but not be foolish and move too quickly that causes risks we don’t need to deal with.”
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