DUBAI, United Arab Emirates (AP) — Countries once colonized by empires are striking back on global warming — and they have the pope's blessing.

Leaders of developing nations jumped into Saturday's second-day of high-level speeches at the U.N. climate summit to press rich industrial countries to share their knowhow to fight global warming and ease the financial burdens they face — while trumpeting their own natural resources that swallow heat-trapping carbon in the air.

The 28th annual U.N. Conference of the Parties, or COP28, in the oil-rich United Arab Emirates featured about 150 presidents, prime ministers, royals and other leaders who are presenting their plans to cut heat-trapping emissions and mostly seek unity with other nations to avert climate catastrophe that seemed to draw closer than ever in 2023.

Injecting moral authority into the talks, Pope Francis said “the destruction of the environment is an offense against God” in a letter read on his behalf because he had to cancel plans to attend because of a lung inflammation.

In the letter read by Vatican Secretary of State Cardinal Pietro Parolin, Francis noted that almost all of the world that’s “needy” is “responsible for scarcely 10% of toxic emissions, while the gap between the opulent few and the masses of the poor has never been so abysmal.”

“The poor are the real victims of what is happening: we need think only of the plight of Indigenous peoples, deforestation, the tragedies of hunger, water and food insecurity, and forced migration,” the pope’s letter said.

Several African leaders noted their continent's rainforests help gobble up excess carbon dioxide in the air and emphasized how their countries belch out only a tiny fraction of heat-trapping emissions compared to richer countries.

Teodoro Obiang Nguema Mbasogo of Equatorial Guinea — one of sub-Saharan Africa's biggest oil producers — faulted developed nations for failing to deliver on their pledges to meet their commitments on financing for climate action and meet their own targets to curb their industries' emissions.

President Jose Ramos Horta of Timor-Leste, next to Indonesia and north of Australia, blasted “shark loans” from multilateral lending institutions, saying developing nations cannot recover from heavy debt burdens that squelch their ability to put money into fighting climate change and grow economically.

Later Saturday, fifty oil companies — representing nearly half of global production — pledged to reach near-zero methane emissions and end routine flaring in their operations by 2030, Sultan al-Jaber, the president of this year’s United Nations climate talks, said. The companies also signed up to reach “net zero” for their operational emissions by 2050.

The pledge includes national oil companies like Saudi Arabia's Aramco, Brazil's Petrobras, and the Abu Dhabi National Oil Co., of which al-Jaber is head, as well as multi-nationals like Shell, BP and TotalEnergies.

But a letter signed by over 300 civil society groups criticized the announcement as a “smokescreen to hide the reality that we need to phase out oil, gas and coal."

With U.S. President Joe Biden staying home, Kamala Harris became the first vice president to lead America’s delegation since Al Gore — now a major climate activist — at COP3 in 1997.

She said the United States is pledging $3 billion to the Green Climate Fund, which helps developing countries access capital to invest in clean energy and “nature-based solutions,” cautioned that the world was facing a “pivotal moment” in the fight against global warming. In a written statement, the U.S. Treasury said the pledge is subject to funding availability.

“Our action collectively — or worse — our inaction, today, will impact billions of people for decades to come,” she said in brief remarks — well under her allotted time — to a main floor of gathered leaders that featured scores of empty seats. “For as much we as have accomplished, there still is so much more work to do, and continued progress will not be possible in without a fight.”

Later, in remarks with smaller groups of leaders, Harris was expected to say that the U.S. plans to join 90 nations in a pledge to double energy efficiency and triple renewable energy capacity by 2030 — a goal she says the United States is now on track to meet with these latest investments, according to U.S. officials.

As Harris made her way toward the Dubai venue earlier Saturday, U.S. climate envoy John Kerry and French President Emmanuel Macron pushed for development of nuclear energy — which does not produce greenhouse gas emissions, even if it also presents security and waste challenges.

Overall, a group of more than 20 nations called for a tripling of nuclear energy generated in the world by 2050.

“I want here to reiterate the fact that nuclear energy is a clean energy and it should be repeated,” said Macron, whose country gets around two-thirds of its electricity from nuclear power, the most of any industrialized country, and exports some of it to France's neighbors.

A declaration issued at the event did not specify how much money should be set aside, but urged the World Bank and others to “encourage” expanding lending for nuclear projects.

Kerry later announced that the U.S. was joining the Powering Past Coal Alliance, which means the administration commits to building no new coal plants and phasing out existing plants. It's in line with other Biden regulatory actions and international commitments already in the works had meant no coal by 2035.

Whatever their perspective or national interest, leaders almost universally voiced their shared views that Earth is in crisis — with the United Nations and other environmental groups warning that the planet has recorded the nine hottest years on record over the last decade.

Bolivian Vice President David Choquehuanca called for "saving Mother Earth and staving off the multiple crises which have been caused by neocolonial, capitalist, imperialist, patriarchal, Western culture.”

“The climate crisis is but the latest chapter in a long history of hypocrisy and lies: The ‘Global North' is responsible for the global imbalance that we’re seeing," he said, using a catchall term for industrialized countries. "They seek permanent growth to the detriment of the global South.”

German Chancellor Olaf Scholz said science shows that the world needs to “step up the pace” to battle climate change, but took a more upbeat tone, saying: “We have what it takes to meet these challenges. We have the technologies: wind power, photovoltaics, e-mobility, green hydrogen.”

He said demand for fossil fuels has slowed and the peak is "in sight.”