United Nations Secretary-General Antonio Guterres appealed for a deal from the COP30 climate summit on the hotly-disputed subject of weaning the world off fossil fuels.
The summit in the Amazon city of Belém, Brazil, missed a self-imposed deadline yesterday for a deal to secure agreement among the nearly 200 countries present on issues including how to increase climate finance and shift away from fossil fuels.
Mr Guterres told the negotiations from 194 countries plus the European Union that limiting global warming to 1.5C of warming must be their only red line.
He said this is the hour for leadership and asked them to be bold, to follow the science, to put people before profit, and to please keep their eyes on the finish line.
"I welcome calls for a just transition mechanism and the growing coalition asking for clarity on the transition away from fossil fuel," he told a press conference at the summit.
There are less than 48 hours until the scheduled end of the summit to find a consensus, which host nation Brazil has framed as a crucial step to ramping up climate action and demonstrating that there is broad support to accelerate turning decades of promises and pledges into concrete action.
"One thing is clear, we are down to the wire, and the world is watching Belém," Mr Guterres said.
"I strongly appeal to all delegations to show willingness and flexibility."
The future of fossil fuels has become a focal point for the two-week negotiation.
Watch: Guterres says the 'world is watching Belém'
Taking their cue from Brazil, dozens of countries including both developed and developing nations have mounted a push for a road map setting out how countries should transition away from fossil fuels.
Others, including some fossil fuel producing nations, are resisting.
"Science tells us that a temporary overshoot above 1.5C, starting at the latest in the early 2030s has become inevitable.
"We know what that means - more heat and hunger, more disasters and displacement, and the higher risk of crossing climate tipping points unleashing irreversible damage, including here in the Amazon," Mr Guterres said.
He said however, that the rise in global temperatures can be brought back below 1.5C before the end of this century, if countries act now to make this overshoot as small, short and safe as possible.
The COP28 climate summit in 2023 agreed, after protracted discussion, to a transition, but nations have not mapped out how - or when - it will happen.
"I am perfectly convinced that a compromise is possible," Mr Guterres added.
'This will come down to the wire', says O'Brien
Meanwhile, Minister for Climate, Energy and the Environment Daragh O'Brien said that negotiations at the COP30 climate conference in Brazil "have intensified."
Mr O'Brien, who is attending the summit, said there is "great unity in the EU" towards the talks and that Ireland is "actively involved" in this.
He said there is "positive soundings" but conceded "we don't have an agreement or even a draft final text yet".
He said the focus of COP30 is "implementation", adding that while the Paris Climate Accord committed to capping global temperatures rises to 1.5C, the projections now show this will not be met.
The minister said the figure is going to be "2.3 to 2.5" degrees.
He warned that this range of temperature change would be "catastrophic and irreversible".
He praised the Brazilian presidency of COP for doing an "excellent job" in focusing on what has been agreed up to now.
"How can we accelerate their delivery, how can we actually assist particularly developing states...who are affected most...they are the ones who are least at fault for this crisis," he said.
Mr O'Brien said there seemed to be a "determination" by the 189 countries plus the EU, "to really knuckle down and to get an agreement that will mean that we can really effect positively the changes that we're seeing and reverse some of those changes".
"But this will come down to the wire, I expect," he said.
Additional reporting by George Lee