Story highlights GOP Sen. Jeff Flake said he is not comparing Trump to Stalin directly

He called for other Republicans to speak out when Trump attacks the press

Washington (CNN) GOP Sen. Jeff Flake of Arizona plans to deliver a speech comparing President Donald Trump's attacks on the press as reminiscent of Joseph Stalin, and said Monday that his colleagues should join him in speaking out.

"I hope that more of my colleagues will stand up when the President uses 'fake news,' for example, in ways that I think put journalists across the world in danger," Flake told CNN's Christiane Amanpour.

Flake has been among the most outspoken critics of Trump's statements and policies regarding trade and immigration, and the senator said he plans this week to deliver a speech on the Senate floor attacking Trump for calling mainstream outlets "the enemy of the American People!"

Flake made clear, however, that he did not intend to compare Trump to Stalin but wanted to note that the President's attack on the press as "the enemy of the people" recalled Stalin.

"I am in no way comparing President Trump to Joseph Stalin -- Joseph Stalin was a killer; our President is not," Flake said. "It just puzzles me as to why you would use a phrase that is so loaded and that has such deeper meaning, the press being the enemy of the people."

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