Chebet Maikut, the delegate for Uganda, an East African country recently hit by drought, said undue corporate influence could derail the talks by weakening or delaying emissions goals.
“These corporations are so powerful,” Mr. Maikut said. Uganda’s economy is less than a tenth of the market capitalization of the fossil fuel giant Exxon Mobil, for example. “We need a stronger rule book,” he said.
The Paris climate deal, reached in 2015, commits nearly every country to lowering planet-warming gas emissions to stave off the most severe effects of global warming. But just how to do this needs to be worked out in a series of negotiations.
At a heated session at the latest round of talks on Tuesday, delegates from the United States, Russia and Australia made a last-minute defense of the corporate presence, suggesting that a wider discussion of the issue be delayed.
An American delegate argued that it would be “premature” to continue the discussion over corporate participation at the meeting, said someone at the session, which was abruptly closed to outside observers.
The talks risked becoming “an endless ideas factory,” the American delegate said.
After four hours of debate, delegates agreed to call for suggestions from member nations on how to address the issue, and to take them up next year.
Outside the negotiations, a handful of protesters held signs that read, “Stop Corporate Capture” and “Polluters Out, People In.”
Some environmental groups have argued that the Paris accord does not go far enough, having been watered down by corporate interests that opposed stronger emissions restrictions.
More recently, talks about next steps have been overshadowed by the specter of the Trump administration abandoning the deal.
That is a move even corporations have warned against.
Last week, the chief executives of 30 large American companies, including Dow Chemical and the agricultural giant Cargill, took out a full-page ad in The Wall Street Journal expressing their “strong support” for United States participation in the agreement.
But there may be more to American companies’ support of the Paris process than meets the eye.
American corporations have a strong, self-serving motive for urging the United States not to withdraw, said Tamar Lawrence-Samuel, policy director at Corporate Accountability International, which campaigns against corporate influence in public policy.
“It makes complete sense to be at the policy making table than to be on the outside,” Ms. Lawrence-Samuel said. “For years, these talks have been overrun by the very industries at the very heart of the problem.”
The tussle over corporate influence is occurring at a delicate time.
With the overall deal ratified, nations are now hashing out exactly how they will meet the goal of limiting global warming to 3.6 degrees Fahrenheitabove the preindustrial level.
Industry groups are already seeking a reconsideration of the United States’ commitments.
“This ain’t going to happen,” Stephen D. Eule, a policy specialist at the research arm of the U.S. Chamber of Commerce, said at an event the chamber hosted on Monday in Bonn.
The group routinely sends specialists to the climate negotiations, and includes a Dow Chemical executive on its board of directors. Cargill is also an active member. The companies have checkered environmental records.
The chamber argued against the effectiveness of domestic steps to regulate emissions, and urged the Obama administration to be wary of global emission reduction goals.
A better alternative was “a revised pledge more in line with reality” that would be “much less ambitious,” Mr. Eule said.
At least one participant appeared stunned.
“Listening to you, I have the feeling that you and I exist in alternative universes,” said Ingo Puhl of the International Emissions Trading Association, who argued that a transition toward renewable energy sources was inevitable, for environmental and cost reasons.
In a statement, the chamber contended that a market-based approach and new technologies would continue to lead to carbon emission reductions.
Dow and Cargill said they supported overall measures to reduce emissions.
The effort to curb corporate influence could seek to ban or restrict the attendance at the talks by industry groups, like the U.S. Chamber or the World Coal Association.
It could also ban “revolving door” appointments of industry officials to policy making posts and impose other rules to prevent conflicts of interest.
The influence of tobacco companies was limited at the 2003 Framework Convention on Tobacco Control, which ultimately led to worldwide restrictions on their advertising and sponsorship, supporters say.
Any changes would require the support of a majority of the almost 200 nations and regions that are party to the climate talks.
Norine Kennedy, a vice president at the lobby group United States Council for International Business, said that corporations and the technological solutions they provide needed to be part of any realistic climate settlement.
“The reason we were able to get the Paris agreement in the first place was that the U.N. was willing to open their doors to a whole range of stakeholders, including businesses,” she said.
Many of the biggest polluters at the talks, including the United States, Canada, the European Union and Japan, have been receptive to those concerns.
Trigg Talley, the United States deputy special envoy for climate change and the senior American negotiator in Bonn, called the proponents of the effort to rein in corporate influence “well intentioned but deeply misguided.”
“It’s not a good path to go down,” he said.
Support has grown, however, cutting across several established negotiating blocs at the climate talks, including the Like Minded Developing Countries bloc of about a dozen nations, the Least Developed Country bloc of about 50 nations, and African States.
Another important backer of the effort has been China, which is increasingly replacing the United States as a defender of an ambitious climate change policy. Critics note that China’s biggest enterprises are state-owned, and already have a voice at the negotiating table.
Still, powerful companies are “drowning out the voices of developing nations,” a Chinese delegate argued at a committee on Saturday. “Vulnerable voices must be heard.”