NEWT: Trump's recent campaign behavior is 'very self-destructive'

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Newt Gingrich addresses RNC

Former House Speaker Newt Gingrich characterized Donald Trump's recent campaign behavior as "very self-destructive" on Wednesday and said the Republican nominee is "still behaving" as though he is still "in the primaries."

"He has not made the transition to being the potential president of the United States, which is a much tougher league," Gingrich said on Fox Business Channel's "Mornings with Maria."

He added: "People are going to watch you every single day. They're going to take everything they can out of context, and he is not yet performing at the level that you need to."

See images of Newt Gingrich through the years:

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Newt Gingrich through the years
UNITED STATES FILE PHOTO: Rep. Newt Gingrich, R-Ga., gives a lecture on Sept. 18, 1993 during the first day of his 'Renewing American Civilization' course taught in fall 1993 at Kennesaw State College in Kennesaw, Ga. The course later became part of Congressional ethics violation charges leveled against Gingrich in 1996. (Photo by Bill Clark/Getty Images)
WASHINGTON, DC - JANUARY 5: Newt Gingrich(L), speaker of the US House of Representatives, laughs as US President Bill Clinton(R) looks on during a meeting of the bi-partisan leadership of Congress 05 January at the White House. The day after the opening session of the 104th Congress, Republicans and Democrats met with Clinton to discuss the legislative agenda. (COLOR KEY: Red in ties.) (Photo credit should read J. DAVID AKE/AFP/Getty Images)
CLAREMONT, NH - JUNE 11: President William Jefferson Clinton and Speaker of the House Newt Gingrich, share a laugh at a meeting held at a senior citizens center in Claremont, N.H. (Photo by John Bohn/The Boston Globe via Getty Images)
ME.Gingrich.Newt.RDL (kodak) House speaker Newt Gingrich greets supporters at a fundÂraiser at the Anaheim Hilton and Towers in Anaheim. TIMES (Photo by Robert Lachman/Los Angeles Times via Getty Images)
UNITED STATES - NOVEMBER 15: Former Speaker of the House Newt Gingrich, R-Ga., speaks during the ceremony to unveil his portrait in Statuary Hall. (Photo By Douglas Graham/Roll Call/Getty Images)
WASHINGTON - DECEMBER 17: (AFP OUT) Former U.S. Speaker of the House Rep. Newt Gingrich (R-GA) (L) speaks as he is interviewed by moderator Tim Russert (R) during a taping of 'Meet the Press' at the NBC studios December 17, 2006 in Washington, DC. Gingrich spoke on various topics including the war in Iraq and the 2008 Presidential election. (Photo by Alex Wong/Getty Images for Meet the Press)
WASHINGTON - DECEMBER 06: Newt Gingrich and Callista Gingrich attend the 32nd Kennedy Center Honors at Kennedy Center Hall of States on December 6, 2009 in Washington, DC. (Photo by Kevin Mazur/WireImage)
MANCHESTER, NH - JANUARY 07: Republican presidential candidates (L-R) former Utah Gov. Jon Huntsman Jr., U.S. Rep. Ron Paul (R-TX), former Massachusetts Gov. Mitt Romney, former U.S. Sen. Rick Santorum, former Speaker of the House Newt Gingrich and Texas Gov. Rick Perry participate in the ABC News, Yahoo! News, and WMUR Republican Presidential Debate at Saint Anselm College January 7, 2012 in Manchester, New Hampshire. The GOP contenders are in the final stretch of campaigning for the New Hampshire primary, the first in the nation, to be held on January 10. (Photo by Win McNamee/Getty Images)
WOLFEBORO, NH - JANUARY 07: Republican presidential candidate, former Speaker of the House of Representatives Newt Gingrich speaks during a campaign town hall meeting at the Wright Museum January 7, 2012 in Wolfeboro, New Hampshire. According to a CNN/Time/ORC poll released Friday, Gingrich has dropped from 43-percent in December to 17-percent, putting him even with fellow candidate, former U.S. Senator Rick Santorum. However, both are trailing former Massachusetts Governor Mitt Romney who is polling at 37-percent. (Photo by Chip Somodevilla/Getty Images)
Republican presidential hopefuls, former Massachusetts Govenor Mitt Romney (L), former Speaker of the House Newt Gingrich, take the stage for the NBC News, Tampa Bay Times, National Journal Republican Presidential Candidates Debate at the University of South Florida, January 23, 2012, Tampa, Florida. AFP Photo/Paul J. Richards (Photo credit should read PAUL J. RICHARDS/AFP/Getty Images)
Republican presidential hopeful, former Speaker Newt Gingrich, delivers remarks during a Hispanic Town Hall January 28, 2012 at the Centro de la Familia church in Orlando, Florida AFP Photo/Paul J. Richards (Photo credit should read PAUL J. RICHARDS/AFP/GettyImages)
MESA, AZ - FEBRUARY 22: Republican presidential candidates former Massachusetts Gov. Mitt Romney (L) and former Speaker of the House Newt Gingrich laugh as they participate in a debate sponsored by CNN and the Republican Party of Arizona at the Mesa Arts Center February 22, 2012 in Mesa, Arizona. The debate is the last one scheduled before voters head to the polls in Michigan and Arizona's primaries on February 28 and Super Tuesday on March 6. (Photo by Justin Sullivan/Getty Images)
TAMPA, FL - AUGUST 30: Former Speaker of the House Newt Gingrich and Callista Gingrich speak during a tribute to former president Ronald Reagan at the final day of the Republican National Convention at the Tampa Bay Times Forum on August 30, 2012 in Tampa, Florida. Former Massachusetts Gov. Mitt Romney was nominated as the Republican presidential candidate during the RNC which will conclude today. (Photo by Mark Wilson/Getty Images)
THE TONIGHT SHOW WITH JAY LENO -- (EXCLUSIVE COVERAGE) -- Episode 4289 -- Pictured: (l-r) Newt Gingrich, Nicole 'Snookie' Polizzi, Callista Gingrich backstage on July 18, 2012 -- (Photo by: Margaret Norton/NBC/NBCU Photo Bank via Getty Images)
NATIONAL HARBOR, MD - FEBRUARY 27: Former U.S. Speaker of the House Newt Gingrich (R-GA) addresses the 42nd annual Conservative Political Action Conference (CPAC) February 27, 2015 in National Harbor, Maryland. Conservative activists attended the annual political conference to discuss their agenda. (Photo by Alex Wong/Getty Images)
WASHINGTON, DC - APRIL 25: Former United States Secretary of State Madeleine Albright(L) and Newt Gingrich attend The Washington Post White House Correspondents' Pre-Dinner Reception at The Washington Hilton on April 25, 2015 in Washington, DC. (Photo by Brad Barket/Getty Images)
CINCINNATI, OH- JULY 6: Former Speaker of the House Newt Gingrich (R) introduces Republican Presidential candidate Donald Trump during a rally at the Sharonville Convention Center July 6, 2016, in Cincinnati, Ohio. Trump is campaigning in Ohio ahead of the Republican National Convention in Cleveland next week. (Photo by John Sommers II/Getty Images)
CINCINNATI, OH- JULY 6: Former Speaker of the House Newt Gingrich (R) introduces Republican Presidential candidate Donald Trump during a rally at the Sharonville Convention Center July 6, 2016, in Cincinnati, Ohio. Trump is campaigning in Ohio ahead of the Republican National Convention in Cleveland next week. (Photo by John Sommers II/Getty Images)
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Gingrich, one of Trump's most ardent supporters who was once considered as a possible running mate, said Trump appeared to be going through a phase similar to Joe Montana's "stretch during his career where he kept throwing interceptions."

"It's like watching a team go out on the field, throw an interception on the first play and go back off the field again," Gingrich said.

Gingrich also said he was "totally for" House Speaker Paul Ryan and Arizona Sen. John McCain, both of whom Trump refused to endorse on Tuesday.

"I think he has the potential to win the election. I think he has the potential to be a historic president, but to do that, he has got to grow into the size of the job and not get stuck where he has been, which frankly over the last week, I think has been very disheartening to most of his supporters," he said.

NOW WATCH: Watch Trump relentlessly slam Hillary Clinton in his big RNC speech

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SEE ALSO: Donald Trump declines to endorse Paul Ryan: 'I'm just not quite there yet'


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