President Trump signed a measure Tuesday that could presage the most aggressive assault on government regulations since President Reagan.

The bill cancels out a Securities and Exchange Commission regulation that would have required oil and gas and mining companies to disclose in detail the payments they make to foreign governments in a bid to boost transparency in resource-rich countries.

It is the first of a series of bills Congress is considering that would take advantage of the Congressional Review Act of 1996, which had been used only once before today. The act gives a new president and Congress the power to revoke rules and regulations promulgated by the previous administration in its final 60 legislative days.

The previous time the review act was invoked was in 2001 to overturn a Clinton administration regulation about ergonomics.

“It’s a big deal,” Trump said as he signed the measure in the Oval Office. “The energy jobs are coming back. Lots of people going back to work now.” The White House later issued a background paper saying the measure Trump signed “blocks a misguided regulation from burdening American extraction companies.”

Hill Republicans are also seeking to use the Congressional Review Act to overturn regulations that would: prevent coal-mining operations from dumping waste into nearby waterways; restrict methane emissions by oil and gas operations on federal land; require federal contractors to self-certify that they comply with U.S. labor laws; require each state to issue annual ratings for teacher-prep programs; and introduce a planning rule for federal lands.

House Speaker Paul D. Ryan (R-Wis.), who attended the signing Tuesday, said it would be “the first of many Congressional Review Act bills to be signed into law by President Trump.” He said they would “provide relief for Americans hurt by regulations rushed through at the last minute by the Obama administration.”

But when the Obama administration issued the regulations now under attack, it had said they would protect ordinary Americans and the environment from corporate excesses.

Supporters of the SEC regulation say it would have provided greater transparency. The SEC said Congress had sought transparency “to help combat global corruption and empower citizens of resource-rich countries to hold their governments accountable.” The regulation was drafted in response to directions in the Dodd-Frank financial reform legislation. The directive was in an amendment backed by Sen. Benjamin L. Cardin (D-Md.) and then-Sen. Richard G. Lugar (R-Ind.).

Foes of the regulation, led by the U.S. Chamber of Commerce and the American Petroleum Institute, said the rule would put natural resource companies at a competitive disadvantage to foreign firms by disclosing too much of their contract terms. They also said that compliance would be unduly expensive.

“We think it’s a regulation that would have an unintended consequence of hurting U.S. business’s ability to compete,” Jack Gerard, president of the American Petroleum Institute, said in a recent interview. He said the SEC’s requirement that information be provided on a project basis was particularly objectionable.

His arguments were echoed by the White House, whose background paper said that “the regulation created an unfair advantage for foreign-owned extraction companies.”

But other companies, including Intel and Tiffany & Co. that make use of minerals that are produced in countries mired in conflict, have embraced the policy.

“Today, President Trump is signing his name to a bill with only one clear purpose: to make it easier to get away with corruption,” said Oxfam America’s senior policy adviser for extractive industries Isabel Munilla. “This rule was mandated by Congress, a mandate that remains in force in spite of this senseless bill.” She said the SEC was still under instructions to come up with another rule that would serve the same purpose.

The House resolution was introduced by Rep. Bill Huizenga (R-Mich.), a member of the House Financial Services Committee. In the Senate, the lead sponsor was Sen. James Inhofe (R-Okla.).

At the Oval Office signing ceremony Tuesday, Trump said he planned to take on the Affordable Care Act adopted under President Barack Obama. Turning to Ryan, Trump said that “we’re working on Obamacare,” the shorthand for the Affordable Care Act he and Congress have been struggling to replace as well as repeal. “It will be very soon,” Trump said.

An earlier version incorrectly that the measure was the first piece of legislation signed by Trump. It’s the first that relied on the Congressional Review Act. The story has been updated.