ExxonMobil said on Monday that it would take a series of steps to cut emissions of methane, a potent greenhouse gas, from its U.S. onshore oil and gas production. The measures will include upgrading equipment and finding and repairing leaks.

The announcement comes as the Trump administration is working to postpone and review federal rules that would require similar steps across the industry. Oil and gas trade groups sued to block those rules, saying they were too costly. Now, some environmentalists say Exxon’s move undermines that argument.

“At a time when there are some companies making the argument that the sky is going to fall if they’re required to take sensible action to reduce methane emissions, you have the nation’s largest oil and gas producer simply moving ahead,” said Mark Brownstein, vice president for climate and energy at the Environmental Defense Fund.

“It begins to send a signal to both others in industry and frankly the policymakers that these sorts of things are doable,” he said.

Exxon didn’t disclose how many tons of methane emissions its voluntary measures might prevent. But Brownstein said that based on Exxon’s announcement, the steps could go even farther than the federal rules require, because they would apply to both new and existing facilities on private lands as well as public lands.

Trump Chips Away at Obama-Era Rules

Methane, the main component of natural gas, is a potent short-lived climate pollutant that is 28 to 34 times more effective at trapping heat than CO2 over the course of a century. It accounts for about 10 percent of U.S. greenhouse gas emissions, and the oil and gas sector is the largest source in this country.

The Obama administration had tried to address this in part by passing two rules to limit emissions—one through the EPA that applies nationwide but only to new operations, and another, through the Bureau of Land Management, that applies to new and existing operations on federal lands. The Trump administration has said it’s reviewing the rules, and it is widely expected to weaken them. The BLM has postponed its rule for two years, while the EPA has proposed doing the same. Environmentalists and some states have sued to overturn the delays. In May, the Senate rejected an attempt to repeal the BLM rule.

Better Technology, Fewer Emissions

In its announcement, Exxon said that over three years it would phase out the use of “high-bleed” valves, which regulate pressure in equipment by venting gas to the atmosphere, at its subsidiary XTO Energy, which operates its shale and other unconventional drilling. It also said it would develop new technology to better detect leaks and expand training and the sharing of best practices.

Exxon made no mention of climate change in the announcement and did not give a reason for the moves beyond characterizing them as an expansion of its existing program to reduce emissions “as a matter of safety and environmental responsibility.” XTO Energy President Sara Ortwein wrote that the decision to reduce methane emissions followed years of research and testing.

Brownstein, whose group has worked with Exxon to study methane emissions, said it’s in the company’s long-term interest to limit emissions.

“Any company with an investment time horizon greater than a year has to know that ultimately, managing methane emissions is going to be part of the business agenda,” he said.

Last month, Politico reported that some executives and lobbyists in the oil and gas industry are concerned that the Trump administration’s regulatory rollback may be too aggressive and could risk sparking a backlash, particularly if there is a major accident or spill.