The World Health Organization's Deputy Director General said he is almost "entirely disillusioned with the world" as the women, children and men of Gaza are abandoned.
Dr Mike Ryan said there are certain crises in which circumstances make it difficult to bring assistance to those in need, but this is not the case in Gaza.
"This is a tiny, easily accessible area but we cannot get basic supplies in, and children are being intentionally starved as a weapon of war," he said.
"Hostages need to be released and there needs to be a ceasefire now."
Speaking on RTÉ's Morning Ireland, Dr Ryan commended the people, Government and NGOs of Ireland for their support.
"Hunger and occupation are cultural triggers in our society," he said.
"I just wish to God that they were cultural triggers in other societies because the Irish can't do it alone."
He said overall as a global community "we fail to invest in our children".
"We fail to see that the most dangerous thing to our civilisation and society is someone with nothing left to lose," he said.
Dr Ryan also addressed the issue of child poverty, after the Economic and Social Research Institute reported that one in five children are living below the poverty line after housing costs are taken into account.
Dr Ryan said: "We are leaving a lot of children behind us."
He said that poverty is not measured simply through the "bottom line of euros left in your pocket" but includes poverty of environment, exclusion, isolation and mental health.
Dr Ryan said the Government was at least trying to deal with the issues of child poverty in a multi-dimensional way and trying to create environments in which children can thrive.
Universal measures are also needed, he said.
"I don't think I'd ever got to college without free access to medicine, free access to dentists, our free education system," said Dr Ryan.
"We've done this before as a society in the 1960s, we realised we needed to educate a new generation, we needed to change what we did."
"We need to ask children what they need and we need to invest in communities that serve those children," he added.
Covid had 'massive effect' on children, says Ryan
Meanwhile, Dr Ryan said that Covid had a "massive effect" on children.
He said WHO never advised lockdowns and favoured targeted measures.
"We [WHO] never advised lockdowns," Dr Ryan said. "Lockdowns were a construct that countries themselves came up with."
"At no point did we advise lockdowns," he said.
Dr Ryan said the anti-vaccination movement existed before Covid but it has amplified since the pandemic.
"I believe that human beings have the right to question what is put into their bodies," he said.
However, he said anti-vaccination should not be turned into an ideological concept where people are manipulated with false information.
"We need to have a healthy debate but we also need to trust science and when the data tells us that these are safe and highly effective interventions," he said.
'Vaccines have saved more lives on this planet than any other intervention ever in the history of our civilisation," he said.
"Hundreds of millions, billions of children have been saved over time."
Dr Ryan said that overall vaccinations rates in Ireland are high, adding that he hopes this trend continues.
Ryan approached for Presidential Election run
The Sligo-born epidemiologist also said a number of people had talked to him about running for President.
"I am a great fan of the Presidency", he said,
"While I am very proud of my own achievements, I don't think I sit among those exalted people."
"I just hope that Ireland makes the right choice, and we use this election to re-affirm who we are," he said.
"I think the President reflects the values of society not the politics."
Dr Ryan, who is retiring on Friday, said the death of the Irish Director of WHO’s Polio Eradication Programme, Aidan O’Leary made him think about his own family and future.
"I thought he was bullet proof", he said.
"It's a year since he passed, and others have passed, and eventually you say to yourself, I'm not immortal.
"I need to take time to recover and then see what I want to do when I grow up."
