Rhode Island Sen. Sheldon Whitehouse, the top Democrat on the Senate Environment and Public Works Committee, said recent layoffs at EPA, coupled with Zeldin's comments about sharp spending cuts, show he had no intent to follow through on a pledge during his confirmation hearing to work collaboratively with EPA's staff.

The president also said EPA has found "a lot of people that didn't exist" at the agency, but did not elaborate.

The White House told federal agencies to submit plans by March 13 for “large-scale reductions in force,” the first phase of an effort to drastically reduce the size of the US government.