Testifying before Congress, Pruitt — who earlier said he would recuse himself from working on active litigation related to the rule — said that the agency would "provide clarity" by "withdrawing" the rule and reverting standards to those adopted in 2008.

Pruitt, as Oklahoma attorney general, had sued EPA over the regulation, saying it "usurps" state authority, "unlawfully broadens" the definition of waters of the United States and imposes "numerous and costly obligations" on landowners.

A withdrawal was expected, based on the executive order Trump signed in February targeting the rule. But this is the first clear signal of how the EPA will act on the president's order.