(CNN) Democratic Sen. Bob Menendez of New Jersey warned Monday that Interior Secretary Ryan Zinke is moving toward a "lily-white" agency with his reported lack of emphasis on racial diversity within his department.

"We can find some of the best people in the nation from diverse communities, whether that diversity is ethnically, racially or otherwise," Menendez told CNN's Erin Burnett on "OutFront."

Several employees at the Interior Department have told CNN that Zinke repeatedly has said he won't focus on diversity, an apparent talking point that has upset many people within the agency.

Three high-ranking Interior officials from three different divisions said that Zinke has made several comments with a similar theme, saying "diversity isn't important," or "I don't care about diversity," or "I don't really think that's important anymore."

Menendez said he's concerned the problem exists in many agencies within President Donald Trump's Cabinet as well as the Interior Department.

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