President Michael D Higgins has described the current food and humanitarian distribution system in Gaza as "bogus".
Israel has faced growing international pressure to end its war in Gaza, which was triggered by the unprecedented 7 October 2023 attack by Hamas on Israeli soil.
Scrutiny has increased over flailing aid distribution in Gaza, which Israel blocked for more than two months before allowing a small number of UN vehicles to enter in mid-May.
The United Nations said that was not enough to meet the humanitarian needs.
The US/Israeli-backed Gaza Humanitarian Foundation (GHF) has said it will open two aid distribution centres.
The group, which has been fiercely criticised by humanitarian organisations including the United Nations, began distributing aid last week.
However, it shut its facilities yesterday as the Israeli army warned that roads leading to distribution centres were "considered combat zones".
Speaking today in Galway at the commemoration of 25 years of Terryland Forest Park, President Higgins said he could not speak about green open recreational spaces without referring to the situation in Gaza.
He said the "bogus" humanitarian distribution sector of Gaza is now "regarded as a zone of conflict".
He said: "Before the conflict in Gaza it was the densest population in the planet - 5,500 people per square kilometre.
"After all the displacements, it's 30,000 people per square kilometre - pushed in on top of each other. 8% of the land is capable of being used again for food next year.
"This dispossession, this action, the idea that the bogus humanitarian distribution sector is now regarded as a zone of conflict.
"So you have to make the choice: will you risk your life for your children or will you go without bread. This to my mind is species failure, the great moral collapse.
"And those who say it is of our nature, they are contradicting the very definition of humanity."
President Higgins also referred to yesterday's vote at the UN Security Council, where 14 of the 15 members voted in favour of an immediate, conditional and permanent ceasefire in Gaza.
However, the US vetoed the resolution, saying it undermined ongoing diplomacy.
President Higgins said: "We are now in a very dangerous uncontrolled place where you can say anything.
"You can threaten to limit people’s right to move, their ability go get food.
"On that issue there cannot be equivocation and the UN General Assembly has a right under United for Peace to take an initiative that will overrule the Security Council, and will say if you sign international law, you have not only put your signature on a piece of paper, you take on the duty of implementation - that will be my conversation with people between now and next week."
Tánaiste Simon Harris also described the failure to pass the resolution as "deeply disappointing".
He said: "Israel must stop blocking aid to the people of Gaza. Ireland also strongly supports the resolution's call for an immediate ceasefire and release of all hostages.
"It is clear that a majority of the UN’s members are united in a desire to bring the current suffering to an end. Ireland will continue to work with partners to do everything we can to address the catastrophic situation in Gaza."
Meanwhile, President Higgins said he believes the decision by Trinity College to sever all links with Israeli organisations was arrived at after very careful consideration of all the issues.
"This started with student action but I believe Trinity have made their decision and intend to implement it.
"It's important to put it in the context of what’s happening in the US, where the most prestigious universities are now under threat. I think [the decision by Trinity] was a practical decision which was based in idealism. They carefully considered all aspects in their decision-making process," he added.