The Agriculture Minister has apologised "unreservedly" for attending a function for 80 people on Wednesday night.
Fianna Fáil's Dara Calleary says he "should not have attended" the event at a hotel, just 24 hours after the new COVID-19 measures were introduced.
It comes after The Irish Examiner reported that more than 80 people attended an Oireachtas Golf Society event in Co Galway.
Minister Calleary and a number of other Oireachtas members are among those who are said to have been on the guest list.
The hotel in question told the Examiner that the event was divided into two groups, so the diners were divided into two groups smaller than 50 people.
The space is said to have been divided by a petition - described as a "proper physical structure that divides two rooms".
Minister Calleary has this evening said he should not have attended given the updated public health advice.
He said: "Last night I attended a function I committed to a number of weeks ago, having been asked to pay tribute to a person I respected and admired greatly.
"In light of the updated public health guidance this week I should not have attended the event.
"I wish to apologise unreservedly to the public, from whom we are asking quite a lot at this difficult time. I also offer this apology and my sincere regret to my government colleagues.”
Current guidelines say that no more than 50 people should gather indoors, while there should be a maximum of six people at any table in restaurants.