Former president of Ireland Mary Robinson has said COP28 is going to be difficult.
It also has a presidency that is "somewhat compromised which doesn't help," she added.
Speaking ahead of the annual United Nations Climate Change Conference, which begins in Dubai later this week, Mrs Robinson said it will be important to keep a watchful eye on the global stocktake that will be taking place.
Governments agreed in Paris to carry out a stocktake of their nationally determined contributions, but she warned some countries are beginning to lapse.
She said: "The countries that are emitters - and they include the historic emitters, countries like ours, that built our economies on fossil fuel. We are way behind. And, actually, we are seeing lapsing now.
"We are seeing it in Sweden with tax cuts, we are seeing it in the UK with new permits for oil and gas, we are seeing it in the US despite the Inflation Reduction Act.
"This has stimulated clean energy, but President Biden is licensing permits more than President Trump did.
"And Brazil is doing the same. And China, although it is very good on clean energy, is also opening more coal because it is having shortages in certain parts, and India is doing the same."
Climate legislation
Addressing those gathered for UCC's first Sustainable Futures Forum, Mrs Robinson, who currently chairs a group of experienced former politicians known as The Elders, said the world needs governments to take their responsibilities seriously.
She added: "Ireland is one of them. We have good climate legislation, but we know that despite a lot of effort, it is not enough because we are still only going to cut our emissions by 29% by 2030 by present forecasts. Not 51% or going up to 55% which is what we should be doing."
"That's the scale of the gap we have to fill", she told the audience of academics, students and industry representatives gathered at the Lewis Glucksman Gallery in Cork for the conference.
Chair of UCC's Sustainable Futures Project Dr Marguerite Nyhan put it to Mrs Robinson that while a global target of providing 100,000 billion US dollars per year to help developing countries reduce their emission and build resilience to climate change was agreed at Copenhagen COP 15, this target has consistently been missed by richer countries.
Mrs Robinson said it has been a problem of trust, but it is her understanding that this year it will be met or at least be just short of the figure.
She added: "That (sum) is almost irrelevant. As you heard from the World Bank, we need trillions. But that $100,000 billion is the public money that takes the risk out of investment and gets the private sector in and that is why it is so important. It is a trigger for the trillions that are needed."
She would argue, she said, that we are on the cusp of clean energy, a healthier, safer, climate-safe world that is far fairer.
Mrs Robinson said: "We are literarily on the cusp of it, but we are not moving fast enough.
COP28: Radical change needed to address climate crisis
"The way to solve this is to put a marker in the ground at this COP: Phase out fossil fuel with just transition. Then we move everything much more quickly including at national level, including here in Ireland.
"It is a moment in human history we have never had before. We have to be positive about the fact. All we have to do is go faster into clean energy which is the solution, and nature based regenerative agriculture."
She said her final message for global leaders is that this is happening on your watch.
"I think it is absolutely time to be phasing out fossil fuel with a just transition for the workers and communities affected, and a just transition into an affordable, accessible, clean energy world and nature-generated world that will be so much better", she said.
Clean energy
She said humans need to consume less and that "doesn't mean we have to be unhappy or deprived".
"We can still live a very good life, but it is a matter of the circular economy including not wasting materials, including food," she added.
However, she said that today, clean energy is not affordable enough in Ireland or in other countries.
Mrs Robinson said: "It is not affordable enough because we haven't actually incentivised enough that it will be affordable, whether it is retrofitting houses, electric cars, whether it is changing your heating. This is too expensive for people and they are not willing to do it.
"In fairness to President (Joe) Biden, who I criticised earlier with his Inflation Reduction Act, he has actually incentivised clean energy, and clean energy jobs, in an enormous way.
"We can all learn lessons from that."