Story highlights Mexico's former president, Vicente Fox criticized the country's current president and Donald Trump

Fox and Trump have had a tense relationship throughout the campaign cycle

(CNN) Mexico's former president Vicente Fox slammed the expected meeting Wednesday between Donald Trump and the country's current president, saying "I apologize for our president taking this step forward" and calling it "a desperate move."

Fox lit into Enrique Peña Nieto on CNN's "New Day" for inviting Trump to the country for a high-profile meeting, warning Peña Nieto that the meeting was a serious political risk, and continued his harsh criticism of Trump.

"I don't understand what's going on here, and I really apologize for our president taking this step forward," Fox told CNN's Chris Cuomo. "I will not understand unless there's an explanation to it."

"I think President Peña (Nieto) is taking an enormous political risk by hosting Trump. If he's perceived as going soft on Trump, it will hurt him greatly. He will even be considered like a traitor because we don't accept to be offended like we just heard, and it should not happen that he comes here with a smile on his face. I think this is a big mistake on the part of President Peña."

Fox has made a name for himself as one of Trump's roughest critics. He called Trump a "false prophet" and said the GOP nominee heralded the return "to the era of the ugly American" during an interview in May. Most famously, Fox cursed on live television while talking about Trump and his proposed border wall in February, telling Fox Business' Maria Bartiromo, "I'm not going to pay for that f---ing wall."

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