Former House Speaker Newt Gingrich (R-Ga.) criticized President Trump on Sunday for "mishandling" the release of Deputy Attorney General Rod Rosenstein's memo outlining the firing of former FBI Director James Comey.

"First of all, I urge everybody to read the original Rosenstein memo about Comey, which Trump totally mishandled," Gingrich said during a panel on "Fox News Sunday," according to the Washington Examiner.

Gingrich said Trump should have released the memo "in a state of shock."

"Let the country, through Sunday talk shows, deal with the memo. It's devastating. It's clear that if you got that memo and you're the president, you would have fired Comey," Gingrich said.

Gingrich was referring to the three-page memo that Rosenstein wrote in May 2017 after Trump announced he had fired Comey, entitled "Restoring Public Confidence in the FBI."

Rosenstein wrote that he "cannot defend the Director's handling of the conclusion of the investigation of Secretary Clinton's emails, and I do not understand his refusal to accept the nearly universal judgment that he was mistaken."

Gingrich, a vocal Trump ally, has ripped Rosenstein and the FBI, as well as special counsel Robert Mueller and his ongoing investigation into possible ties between the Trump campaign and Russia.

Last week, Gingrich called Mueller's probe a "breakdown" of the U.S. Constitution.