Olympic Federation of Ireland chief executive Peter Sherrard is "absolutely" confident that the Tokyo Games will go ahead.
Concerns have been growing about a fourth wave of Covid-19 in Japan ahead of the Games, which start on 23 July.
On Thursday European Commission president Ursula von der Leyen said the European Union had authorised the export to Japan of more than 100 million vaccine doses, enough to inoculate about 40% of the population.
Speaking on RTÉ's Late Late Show, Sherrard said: "Obviously, you have to keep a close eye on it. You do have to put it in context.
"[Japan currently has] about four and a half thousand cases daily but in a population of about 120 million that translates back to about 180, 190 here so it is a challenge for them.
"They’ve been dealing exceptionally well with Covid until this point in time.
"It’s something that we are all very conscious of, the protocols are there, the athletes have been competing for the last year in this kind of environment.
"With the [team] vaccinations it’s a big help so a lot of the athletes will have benefitted from the agreement that the IOC reached with Pfizer recently and are able to start the vaccination roll-out.
"That’s certainly a help and it’s been a big source of anxiety for a lot of athletes because they’ve been preparing, going to competition.
"They know at this stage, this far out from Tokyo, if they were to be Covid positive it’s very difficult, it will have a detrimental effect so the roll-out of that vaccination programme will help."
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Asked if he was confident that the Games, which were postponed once already, would proceed, he said: "Yes, absolutely."
On the question of what would constitute a reasonable medal haul, Sherrard said: "If we came back with between three and six we'd be doing extremely well."