If there was a theme for the second day of COP29, the U.N. climate conference in Azerbaijan, it would be mixed messaging from world leaders. As some nations announced ambitious new climate goals, others justified their continued reliance on fossil fuels. The developments come when the world is questioning the United States' future commitment to climate progress in light of President-elect Donald Trump's previous comments about climate change and his selection for EPA administrator.

During his remarks, Azerbaijani President Ilham Aliyev, whose country is hosting the event, defended the use of fossil fuels, calling oil a "a gift of the God" and saying that it is just like any other natural resource. He added that countries "should not be blamed for bringing these resources to the market."

"To accuse us that we have oil is the same like to accuse us that we have more than 250 sunny days in Baku," said Aliyev.

Aliyev also called Western countries hypocrites for decrying oil production and calling for an end to fossil fuel use while still buying oil from countries like Azerbaijan. The European Commission signed an agreement with Azerbaijan in 2022 to receive oil from them when they stopped getting it from Russia. He said double standards are the "modus operandi" for climate talks.

Aliyev's pro-oil statements aren't expected to sidetrack the negotiations. David Waskow, director of international climate action at World Resources Institute, said statements from world leaders "in a sense float above the COP."

But Aliyev's comments added fuel to the criticism that oil-producing states shouldn't be hosting a global climate conference. The United Arab Emirates, another country with significant oil production, hosted last year's event.

Baku is also not an easy place to get to. Conference-goers had to travel by plane because all land routes are closed. A recent study identified that 291 private plane flights to COP28 in Dubai generated 3.8 kilotons of CO2.

How does a nation that touts the excellence of oil and gas end up as the host of an incredibly consequential climate conference?

The answer is entirely procedural. Each year, one of the five U.N. regional groups is selected on a rotational basis to host next year's conference. Group members choose which country will host based on logistics and ability. As a result, champions of climate progress and oil-rich countries are equally likely to host the global climate conference.

Unlike the Azerbaijani president's call to maintain the status quo, U.N. Secretary-General António Guterres stressed the urgency and stakes of controlling global emissions.

"We are in the final countdown to limit global temperature rise to 1.5 degrees Celsius and time is not on our side," the Secretary-General said, urging countries to commit legislatively and financially to the climate response.

He called 2024 "a masterclass in climate destruction," pointing out all of the climate records broken during the year, including the hottest day and months on record, adding that "this is almost certain to be the hottest year on record."

-ABC News' Charlotte Slovin and ABC News Climate Unit's Matthew Glasser

Some of the world's largest greenhouse gas emitters have announced their plans to reduce emissions at the ongoing United Nations climate conference, COP29, in Baku, Azerbaijan.

Although not due until 2025, The United Kingdom, Brazil and the United Arab Emirates released their respective Nationally Determined Contribution (NDC) targets at the conference, marking ambitious plans to reduce their climate impacts.

Under the Paris Agreement, participating countries are required to release their NDCs every five years as part of the goal of limiting global warming to 1.5 degrees Celsius above pre-industrial levels.

"The U.K., Brazil and the UAE are the first major emitters to put forward new national climate commitments, which are the main vehicle for countries to collectively reduce greenhouse gas emissions and avoid catastrophic climate impacts," Melanie Robinson, global director of climate, economics and finance at World Resources Institute said of the announcements.

"Encouragingly, these three nations' new climate targets could put them on a path to reach net-zero emissions by 2050 if their highest ambitions are realized," Robison said.

The U.K. goal aims to reduce the nation's greenhouse gas emissions by at least 81%, compared to their 1990 levels.

The Brazilian government is expected to release its NDC on Wednesday. In a preview announcement, the country said it's committed to reducing net greenhouse gas emissions by 59% to 67%.

"This commitment will allow Brazil to advance towards climate neutrality by 2050, the long-term target of the climate commitment," the government wrote in a statement Monday night. "The NDC results from an extensive assessment of Brazil's emission scenarios. It acknowledges the urgency of combating the climate crisis, addresses the need to build resilience, and sets a roadmap for a low-carbon future for Brazil's society, economy, and ecosystems."

In the UAE's NDC, released last week, the nation sets an emissions reduction target of 47% by 2035, compared to 2019.

"The UAE's third NDC outlines a unified vision for addressing climate change that is aligned and informed by the UAE Consensus adopted at COP28," the UAE wrote in its newest NDC. "The UAE Consensus emphasizes the need for accelerated action across all pillars of the Paris Agreement and serves as a roadmap for enhancing mitigation ambition, scaling up adaptation efforts, and aligning financial flows with low-carbon, climate-resilient development pathways."

"I think when you look at these in the aggregate, what we're seeing is that if these countries really pursue the full extent of what they've committed to, that they would be on track to achieve their net zero targets at mid-century," said David Waskow, director of international climate action at the World Resources Institute, during a press call.

"With all three of them, there's an important question about actually implementing them, and we're going to need to see strong policies and investments," Waskow added.

WRI's Robinson also expressed skepticism about the announcements.

"While these initial 2035 targets look good on paper, they won't move the needle unless countries take bold and immediate steps to turn them into action. The true measure of progress will be whether countries back up their promises with transformative policies and investments that embed climate action at the core of their economic strategies," said Robinson.

-ABC News Climate Unit's Kelly Livingston

For the first time, high-emitting oil and gas facilities will have to pay a fee for emitting a potent greenhouse gas if those emissions exceed a certain level set by the U.S. Environmental Production Agency (EPA).

The new rule, finalized on Tuesday, was announced by John Podesta, the top U.S. climate representative at COP29, the annual U.N. climate conference in Baku, Azerbaijan.

The regulation would cap the amount of methane that certain oil and gas facilities could release into the atmosphere. The companies will be charged a fee for each metric ton of methane exceeding that limit, starting at $900 per metric ton, increasing to $1,200 in 2025 and $1,500 in 2026.

EPA administrator Michael S. Regan wrote in a statement, "EPA has been engaging with industry, states, and communities to reduce methane emissions so that natural gas ultimately makes it to consumers as usable fuel — instead of as a harmful greenhouse gas."

He added, "Along with EPA's complementary set of technology standards and historic financial and technical resources under the Inflation Reduction Act, today's action ensures that America continues to lead in deploying technologies and innovations that lower our emissions."

The EPA estimates the new rule will reduce methane emissions by 1.2 million metric tons through 2035. That's the equivalent of taking 8 million gas-powered cars off the road for an entire year, according to the agency.

The EPA classifies methane as a "super pollutant" and says that over 100 years, one ton of methane released into the atmosphere "traps 28 times as much heat in the Earth system as one ton of emitted carbon dioxide." On a 20-year time scale, it's 84 times more potent, according to the European Union.

The EPA said the oil and natural gas industry is the largest industrial source of the greenhouse gas.

During a press call, David Waskow, director of international climate action at the World Resources Institute, said, "Large oil and gas companies actually supported the fee approach, and I think that they're aiming to make sure that methane, which has been a sort of sore spot in the oil and gas industry, is cleaned up as a way of helping the reputation of the oil and gas industry."

Waskow said that even if the incoming Trump administration tries to undo the regulation, he believes its support within the industry may help keep it in place.

-ABC News Climate Unit's Matthew Glasser

How much will it cost to fight climate change globally, and who should pay for it? That's the primary issue facing delegates at the annual U.N. climate conference, COP29. Dubbed the "finance COP," the two-week event began on Monday in Baku, Azerbaijan.

While representatives from nations worldwide will discuss various climate issues, finance is a key theme this year, namely how much external financing will be available to developing countries for their climate adaptation efforts and to compensate them for the damage and loss caused by climate change. Although wealthier countries generate the majority of greenhouse gas emissions, poorer nations are disproportionately impacted by the consequences of global warming.

Conference attendees and climate leaders will be watching closely the climate investment commitments made by various nations and private finance, and much of the discussion will revolve around who should be paying and how much they should be contributing.

The current target for international public and private financing is around $100 billion, but the U.N. estimates that it will take as much as $2.4 trillion by 2030 to meet climate goals, with $1 trillion coming from international sources.

It's uncertain, however, how much each nation will contribute and where the money will go.

"For those poorest countries and particularly for adaptation, finance needs to be in grant and concessional form," said Melanie Robinson, the global climate, economics and finance program director at the World Resources Institute.

One issue sure to be controversial is whether developing countries that can afford to contribute to the global effort should be added to the contributor base. Critics of that recommendation say the biggest emitters should be the most significant contributors.

U.N. Climate Change Executive Secretary Simon Stiell set the table for the talks during his opening address, focusing on what's at stake.

"If at least two-thirds of the world's nations cannot afford to cut emissions quickly, then every nation pays a brutal price," said Stiell. "If nations can't build resilience into supply chains, the entire global economy will be brought to its knees. No country is immune."

Stiell added, "So, let's dispense with the idea that climate finance is charity. An ambitious new climate finance goal is entirely in the self-interest of every single nation, including the largest and wealthiest."

On the same day Stiell was delivering his remarks, preliminary data from the World Meteorological Organization showed that 2024 remains on track to be the warmest year on record and will likely become the first year that is more than 1.5 degrees Celsius warmer than the 1850 to 1900 pre-industrial average

COP29 takes place in the shadow of significant political challenges, including changes in worldwide political leanings and the recent presidential election in the U.S. It didn't help that delegates had to delay the convention activities on Monday because leaders couldn't agree on a conference agenda. Who would be leading financial planning meetings, as well as an unconventional move from a supervisory board to pass new standards without any consultation, were the primary sources of contestation.

Mukhtar Babayev, president of COP29 and Azerbaijan minister of ecology and natural resources, suspended sessions for further talks on the agenda.

"The hour is late, we have a lot of work ahead of us," Babayev said as the delayed session resumed.

-ABC News' Charlotte Slovin and ABC News Climate Unit's Matthew Glasser