UN Secretary-General Ant nio Guterres gives a speech during the COP27 U.N. Climate Summit, in Sharm el-Sheikh, Egypt, Monday, Nov. 7, 2022.
Nearly 100 heads of state and government are meeting for two days in Egypt's Red Sea resort of Sharm el-Sheikh, facing calls to deepen emissions cuts and financially back developing countries already devastated by the effects of rising temperatures.
"Humanity has a choice: cooperate or perish," Guterres told the UN COP27 summit.
"It is either a Climate Solidarity Pact or a Collective Suicide Pact," he added.
Guterres urged the world to ramp up the transition to renewable energy, and for richer polluting nations to come to the aid of poorer countries least responsible for heat-trapping emissions.
He said the target should be to provide renewable and affordable energy for all, calling on the United States and China in particular to lead the way.
US-Sino tensions, however, have prompted Beijing to freeze climate cooperation with Washington.
President Xi Jinping is absent from the summit, while President Joe Biden will attend it later this week after US midterm elections.
Nations worldwide are coping with increasingly intense natural disasters that have taken thousands of lives this year and cost billions of dollars.
They range from devastating floods in Nigeria and Pakistan to droughts in the United States and several African nations, as well as unprecedented heatwaves across three continents.
"We have seen one catastrophe after another," said Egyptian President Abdel Fattah al-Sisi. "Is it not high time to put an end to all this suffering?"
Money has emerged as a major issue at COP27, with wealthy countries scolded for failing to fulfil their pledge to provide $100 billion per year to help developing countries green their economies.
This is a "major cause for persisting distrust, and neither is there any sound reason for the continuing pollution", said Kenyan President William Ruto, who announced an African climate summit for next year.
A salvo of crises -- from Russia's invasion of Ukraine to soaring inflation and the lingering effects of the Covid pandemic -- have raised concerns that climate change has dropped down the priority list of governments.
'Highway to climate hell'
British Prime Minister Rishi Sunak said President Vladimir Putin's "abhorrent war in Ukraine and rising energy prices across the world are not a reason to go slow on climate change."
German Chancellor Olaf Scholz, whose gas-dependent economy has been squeezed hard by cuts in Russian supplies, also warned against a "worldwide renaissance of fossil fuels"
Guterres called for a "historic" deal between rich emitters and emerging economies, with countries doubling down on emissions reductions to hold the rise in temperatures to the more ambitions Paris Agreement target of 1.5 degrees Celsius above the pre-industrial era.
Current trends would see carbon pollution increase 10 percent by the end of the decade and put the world on a path to heat up to 2.8C.
"We are on a highway to climate hell with our foot still on the accelerator," Guterres said.
Poorer countries successfully fought to have the issue of "loss and damage" -- compensation for the damage caused by climate-enhanced natural disasters -- officially put on the COP27 agenda.
"We, the oceanic states that suffer the harsh effects of your activities, have to be assisted in repairing the damage you cause to us," said Seychelles President Wavel Ramkalawan, whose island nation is threatened by rising waters.
Barbados Prime Minister Mia Mottley called for a windfall tax on the profits of oil companies, that would be funnelled to a loss and damage fund.
The United States and the European Union have dragged their feet for years on compensation for climate impacts, fearing it would create an open-ended reparations framework.
"Loss and damage is not an abstract topic of endless dialogue," Ruto said. "It is our daily experience and the living nightmare for hundreds of millions of Africans".
Guterres said that getting "concrete results on loss and damage is a litmus test of the commitment of governments to the success of COP27."
In a possible blueprint for other developing nations, a group of wealthy nations approved a plan paving the way for South Africa to receive $8.5 billion in loans and grants to move away from coal.
COP27 is scheduled to continue through November 18, with ministers joining the fray during the second week.