Dublin will almost certainly be stripped of its Euro 2020 hosting rights on Friday after Ireland's Tanaiste Leo Varadkar admitted it was "too soon" to consider crowds at sports events.
UEFA set an initial deadline of April 7 for the original 12 host cities to provide minimum guarantees of capacity, as it plans for at least a limited number of supporters being in attendance at the games amid the coronavirus pandemic.
Nine of the cities have confirmed their plans but Dublin, along with Bilbao and Munich, have not.
And Varadkar told Today FM on Wednesday: "The last I heard was that the organisers (UEFA) were looking at us to commit to have at least 25 per cent of the stadium full.
"We're cautious about that. We just think June is too soon. I think if they continue to insist on that, it will be hard for that to go ahead which is unfortunate."
UEFA's executive committee had initially been set to take a final decision on Euros hosting on Monday, but the decision of 12 of the continent's top clubs to announce they had signed up to a breakaway Super League forced a delay until Friday.
The committee said on Monday it had tasked the UEFA administration with "drawing up concrete proposals" ahead of a final decision.
The Football Association said England stands ready to host additional games if asked, and it is understood UEFA would not limit itself to playing matches only at existing venues.
There have also been reports that Russia may take on extra matches.