Former Mexican President Vicente Fox said on Wednesday morning that Donald Trump is "not welcome to Mexico" and apologized for current Mexican President Enrique Peña Nieto's invitation.

"We don't like him. We don't want him. We reject his message," Fox said in a CNN interview.

He added: "I don't understand why President Peña has offered this opportunity. I think it's nothing more than a political stunt. Trump is using Mexico, is using President Peña to boost his sinking poll numbers."

Trump's most offensive tweets about Mexico

11 PHOTOS Donald Trump's most offensive tweets about Mexico See Gallery Donald Trump's most offensive tweets about Mexico Throughout his 2016 campaign, Trump offered up some pretty offensive statements about the nation of Mexico and its people... We have got to get our Marine out of that disgusting Mexican jail. Would be so easy if we had a real leader. One tough phone call & he's out The Oscars were a great night for Mexico & why not—they are ripping off the US more than almost any other nation. I have a lawsuit in Mexico’s corrupt court system that I won but so far can’t collect. Don’t do business with Mexico! The Mexican legal system is corrupt, as is much of Mexico. Pay me the money that is owed me now - and stop sending criminals over our border I hope the Mexican judge is more honest than the Mexican businessmen who used the court system to avoid paying me the money they owe me. Mexico's court system corrupt.I want nothing to do with Mexico other than to build an impenetrable WALL and stop them from ripping off U.S. I love the Mexican people, but Mexico is not our friend. They're killing us at the border and they're killing us on jobs and trade. FIGHT! Can you envision Jeb Bush or Hillary Clinton negotiating with 'El Chapo', the Mexican drug lord who escaped from prison? .... El Chapo and the Mexican drug cartels use the border unimpeded like it was a vacuum cleaner, sucking drugs and death right into the U.S. We must build a great wall between Mexico and the United States! https://t.co/05SjuRJFbf Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

Fox, who once said it was "very important" to invite Trump to Mexico, said that Peña Nieto was making a "big mistake" inviting the real-estate magnate. He noted Trump's pledge to deport approximately 11 million immigrants living in the US illegally and force Mexico to fund a physical wall along America's southern border.

"I think President Peña is taking an enormous political risk by hosting Trump," Fox said. "If he's perceived as going soft on Trump, it will hurt him greatly — he will even be considered like a traitor."

Fox said Peña Nieto needs to force Trump to apologize for "stupid proposals" like starting a trade war with Mexico and the deportation force.

Asked about the Trump campaign's recent waffling on key tenants of his immigration pitch to Republican primary voters, Fox said he still didn't believe Trump.

"You cannot trust a guy like this. How can we grant confidence and support to ideas that change every day?" Fox said.

He added: "He's still firm on his stand that he will throw them out, that he will build the wall. He can't play both sides."

Trump immediately responded to Wednesday's interview, noting on Twitter that Fox invited him to visit Mexico earlier this year.

Former President Vicente Fox, who is railing against my visit to Mexico today, also invited me when he apologized for using the "f bomb." — Donald J. Trump (@realDonaldTrump) August 31, 2016

Neither Fox nor Trump have appeared particularly friendly toward one another in the past.

Fox challenged Trump to a debate earlier this year in Mexico, and said that he was "not going to pay for that f------" wall."

Trump responded in kind, demanding the former president apologize for his profanity-laced comments.

'This guy used a filthy, disgusting word on television, and he should be ashamed of himself and he should apologize, okay?" Trump told an audience at a campaign rally in February.

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