President Biden spoke before an overflowing United Nations convention on Friday to stress the U.S. commitment to stop the planet from warming.

The president muscled through a landmark climate law that provides a record $370 billion to accelerate America's transition away from the fossil fuels that have underpinned its economy for 150 years.

He spoke about how he immediately returned the United States to the Paris climate agreement when he took office after Donald J. Trump withdrew the country. He apologized to the group, which included diplomats, ministers and representatives of nearly 200 nations.

In the middle of the two-week summit that has focused not so much on cutting the pollution that is driving climate change, but on the question of what industrialized countries owe poor nations that are suffering climate disasters for which they are ill-prepared, Biden spoke.

At the U.N. climate talks, the idea of climate compensation is being discussed for the first time. The United States and other wealthy nations have blocked calls for loss and damage funding because they worried it would open them up to unlimited liability. It has been difficult to define what loss and damage is and who should pay for it.

Several European countries made cash pledges and supported the creation of a loss and damage fund in order to put pressure on the Americans.

During his visit to Egypt as part of a foreign relations trip that also includes stops in Cambodia and Indonesia, Vice President Joe Biden made no mention of the issue of reparations. Activists and diplomats from developing nations were disappointed by that.

Fatima Denton is a member of the Climate Crisis Advisory Group. As the crisis grows, there will be a solidarity issue here. It's necessary for support for that idea now.

Mr. Biden said that no one was safe from the threat posed by a warming Earth, and that collective action was the only way to deal with it. He called on other nations to increase their efforts to cut pollution that is causing climate change.

The US is acting. Mr. Biden said everyone has to do something. Global leadership has a duty and responsibility. Developing countries should be supported by countries that are in a position to help.

He said that they were racing to do their part to avert the climate hell that the U.N. secretary general warned about.

He promised to give $11.4 billion annually by the year 2024 to help developing countries transition to wind, solar and other renewable energy. Wealthy nations promised that money under the Paris agreement. Mr. Biden was able to get $1 billion from congress last year.

Mr. Biden said that the new climate law in the United States would encourage a cycle of innovation that would reduce costs and improve performance. He said that they would make the transition to a low-carbon future more affordable.

For the first time, Mr. Biden announced, the U.S. government will require domestic oil and gas producers to detect and fix leaks of methane, a greenhouse gas that traps more heat than carbon dioxide in the short run. The fossil fuel industry is the biggest source of methane emissions in the United States because of the odorless gas leaking from the pipes. Scientists say stopping methane from entering the atmosphere is crucial to slowing global warming.

The EPA wants to eliminate 36 million tons of methane emissions from oil and gas operations by the year 2035, more than the amount of carbon dioxide emitted from all coal-fired power plants in a single year.

The United States and Europe led a group of more than 100 countries that agreed to reduce methane emissions. Methane emissions this year are rising faster than ever before according to a report by the World Meteorological Organization. Mr. Biden told other nations to fulfill their promises.

ImageDemonstrators holding up signs at the summit. Some signs say, “Stand with MAPA,” while others say, “Show us the money.”
Demonstrators outside the summit on Friday. One young activist said of Mr. Biden: “He talked about the things America accomplished, but he made it feel like they’ve done enough, and there’s so much more to be done.”Credit...Peter Dejong/Associated Press
Demonstrators holding up signs at the summit. Some signs say, “Stand with MAPA,” while others say, “Show us the money.”

Al Gore said during an interview at the climate talks that Joe Biden is a genuine climate hero.

Mr. Biden said in his speech that he introduced legislation more than 30 years ago to address what was then a looming crisis. The United States will meet its emissions targets by the year 2030.

Even as world leaders welcome American re-engagement on the issue, their expectations for U.S. action have grown.

Ms. Nwuneli said she thought Mr. Biden's speech was disappointing. She said that he made it seem like America had done enough. There are so many more things to be done.

At the climate talks in Egypt, Mr. Biden was the only leader of a major polluter. The president of China, the president of Russia and the prime minister of India did not attend. The absence of the other leaders made Mr. Biden more of a target.

Environmental activists criticized Mr. Biden before his speech. The protesters interrupted it.

The founder of Power Shift Africa said that Mr. Biden's old promises have not been fulfilled after he gave his remarks. He is similar to a salesman who sells goods with little print.

ImageMr. Biden talking with President Abdel Fattah el-Sisi of Egypt. They are both sitting in ornate gold chairs with a matching table with drinks and tissues between them. The American flag is next to Mr. Biden, while the Egyptian flag is next to Mr. el-Sisi.
Mr. Biden meeting with President Abdel Fattah el-Sisi of Egypt before delivering a 23-minute address at the conference.Credit...Doug Mills/The New York Times
Mr. Biden talking with President Abdel Fattah el-Sisi of Egypt. They are both sitting in ornate gold chairs with a matching table with drinks and tissues between them. The American flag is next to Mr. Biden, while the Egyptian flag is next to Mr. el-Sisi.

As soon as the summit began, Mr. Biden stopped. He arrived in Egypt after a night in Washington. The importance of human rights and respect for fundamental freedoms were some of the topics he discussed with the Egyptian president.

He boarded Air Force One for a second overnight flight to Cambodia where he will attend a meeting of the Association of Southeast Asian Nations.

Mr. Biden will travel to Indonesia for the Group of 20 meeting where he will have a discussion with Mr. Xi. Climate activists and diplomats hope that the men who represent the world's two largest economies as well as the two biggest greenhouse gas emitters will restart discussions about climate action. The talks were suspended by China because of Pelosi's visit to Taiwan.

On the ground in Egypt, the president announced modest new steps to build on the tax incentives and government spending programs in the climate law, which is designed to speed the adoption of electric vehicles as well as a transition to wind, solar and other clean energy sources

ImageA landscape view of flares lighting up an oil patch at sunset.
Flaring on an oil field in North Dakota. The Environmental Protection Agency proposed a new regulation on Friday aimed at reducing 36 million tons of methane emissions by 2035.Credit...Isaac Stone Simonelli/The Howard Center for Investigation, via Associated Press
A landscape view of flares lighting up an oil patch at sunset.

There is a provision in the law that threatens fines of up to $1,500 per ton of methane released. The package is meant to help companies avoid fines by spending money on equipment to monitor and contain leaking.

The rule proposed by the E.P.A. requires oil and gas operators to respond to third-party reports of methane leaks at their sites.

The control of Congress could make it difficult for Mr. Biden to pass additional climate legislation. Republican control of one or both chambers of Congress is unlikely to support such spending.

Democratic lawmakers who traveled to Egypt for the summit acknowledged that any new climate efforts would be difficult. It will be very difficult to get it done, according to Senator Whitehouse.

When it comes to funding to help poor countries transition to clean energy or deal with the consequences of climate change, we can't get 60 votes.

Representative Greg Murphy of North Carolina was one of six House Republicans who traveled to Egypt for the summit. He said that Democrats were trying to shift away from fossil fuels too quickly and leave the US at a disadvantage to China.

Mr. Murphy is a former surgeon. If we make a transition that is too fast, we will bankrupt the world.

Lisa Friedman and Jim Tankersley were reporting from Egypt and Cambodia. David Gelles and Max Bearak contributed to the report.

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