The Environmental Protection Agency removed guidance on how states can prove that international pollution affects attainment of air quality standards, promising to examine and possibly relieve transboundary emission regulations, according to a Monday announcement.

The guidance made it “unnecessarily difficult” for states to show that international emitters can affect State Implementation Plans (SIPs) under National Ambient Air Quality Standards, according to an EPA press release.

After this rescission, the agency said it intends “to work with state and local air agencies to develop the evidence necessary to grant regulatory relief” from the regulations at issue under Section 179b of the Clean Air Act.

With that provision, the EPA has the authority to review demonstrations prepared by states that show how they plan to meet US air quality standards—or why they cannot—in the face of pollution coming from other countries.

The guidance rescinded by President Donald Trump gave examples of analyses that could be used for such demonstrations, which in turn could grant reprieve from certain requirements if approved by the EPA.

The move is in line with comments from EPA Administrator Lee Zeldin about not “punishing” states for traveling pollution, as the agency looks to loosen restrictions in an effort to boost Trump’s plans to ramp up fossil fuel energy production.

Zeldin addressed how he plans to address these and other state implementation policies during a recent meeting in Arlington, Va., of the Environmental Council of the States, an organization of state and territorial environmental agency leaders. One goal is to speed SIP approval processes, possibly by transferring EPA scientists from the research office to its air office, he said.

Other issues such as out of state pollution will require flexibility, Zeldin said, adding he’s been very influenced by points Sen. Mark Kelly (D-Ariz.) has raised. “Utah could take every vehicle off the road and be in non-attainment,” Zeldin said. A state that finds itself in a position like that shouldn’t lose out on federal funding due to things outside of its control, he said.

“We will not approach implementation of policies with a one size fits all mindset,” he said.

The EPA will work with states to tailor plans to challenges they face, Zeldin said. That includes thinking through how to address challenges that may arise as foreign-owned operations seek permits, he said.