(CNN) Days after slamming Donald Trump's comments about U.S. District Judge Gonzalo Curiel as "inexcusable," former House Speaker Newt Gingrich stood by the presumptive Republican presidential nominee and called him a "gifted amateur."
Gingrich said Wednesday in an interview with CNN that he believes Trump has made "the kinds of mistakes that amateurs make," but that he is also "learning very, very fast."
"He's learned from it in the last two days and has taken very significant steps away from that and moved toward a more controlled, more civil approach," Gingrich said. "This is what he'll need to win the presidency."
Gingrich forcefully pushed back on reports of his remarks earlier in the day at a conference in California, in which he used the words "absurd amateur" in discussing Trump.
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"I may have said something was an absurd amateur mistake," Gingrich said, as he insisted that his support for Trump remained absolute. "Any effort to take one or two phrases out of the 90-minute dialogue and say, 'Gee, Gingrich was anti-Trump,' is just nonsense."
Gingrich is one of Trump's many supporters who have disavowed the candidate's controversial remarks about Curiel. Trump sparked a firestorm when he suggested that Curiel -- who was born in the United States and is of Mexican heritage -- may be an impartial judge in a Trump University lawsuit given Trump's desire to build a wall along the U.S.-Mexico border and his rhetoric about Mexicans.
Facing criticism from all directions, Trump released a lengthy statement on Tuesday declaring that his comments about Curiel had been "misconstrued" and that he doesn't believe "one's heritage makes them incapable of being impartial."
But in that same statement, Trump also doubled down, saying he feels "justified in questioning whether I am receiving a fair trial." Trump did not offer an apology or walk back his original remarks.
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Gingrich has referred to Trump's comments about Curiel as one of the candidate's "worst mistakes" -- criticism that Gingrich stood by Wednesday's interview with CNN. The former House speaker also added that he personally does not believe that Trump's comments were racist.
"No, I thought they were inappropriate," Gingrich said.
Gingrich is rumored to be on Trump's vice presidential shortlist. Trump declined declined to say what role he might consider Gingrich for in his administration, saying in an interview with Bloomberg Wednesday: "Newt is a very talented guy."
Trump also said his list of potential running mates has narrowed to four or five people, including two military officials.