Washington (CNN) Former Director of National Intelligence James Clapper on Monday accused President Donald Trump of leading "a very disturbing assault on the independence of the Department of Justice."

"When the President -- this president or any president -- tries to use the Department of Justice as kind of a private investigatory body, that's not good for the country," Clapper told CNN's Chris Cuomo on "New Day."

Clapper was reacting to the President's demand over the weekend that the Justice Department "look into" whether the FBI or Justice Department planted a spy in his presidential campaign following reports that the bureau dispatched a confidential source to speak with some campaign aides about possible ties to Russia.

I hereby demand, and will do so officially tomorrow, that the Department of Justice look into whether or not the FBI/DOJ infiltrated or surveilled the Trump Campaign for Political Purposes - and if any such demands or requests were made by people within the Obama Administration! — Donald J. Trump (@realDonaldTrump) May 20, 2018

Clapper defended the FBI's use of confidential informants, calling it "a legitimate activity, an important one, on the part of the FBI. They use informants and have strict rules and protocols on this."

Clapper warned that increased politicization in the oversight of the intelligence agencies "places a heavier burden on our intelligence community leaders to provide the top cover, so that rank-and-file workers, employees in the intelligence community, can continue to serve up truth to power, even if the power doesn't listen to the truth."