Embattled EPA Administrator Scott Pruitt on Tuesday dismissed growing criticism over his connection with a lobbyist whom he paid $50 per night for a bedroom in the lobbyist’s apartment near Capitol Hill, telling Washington Examiner columnist Paul Bedard, "I'm dumbfounded that that’s controversial.”

The backdrop: His remarks come a day after a White House official told the WSJ the administration is digging "a little deeper" to determine if Pruitt's action violated federal ethics rules. On the other hand, Pruitt told Bedard the backlash is part of a concerted effort to undermine President Trump's deregulation agenda, adding: “It’s toxic here in that regard." ABC News first reported the rental controversy last week, which said the lobbyist has clients in industries regulated by the EPA.