Former Mexican President Vicente Fox is a fierce critic of presidential candidate Donald Trump, repeatedly denouncing what he says are his "racist and ignorant ideas." Trump "says that he'll make America great again," Fox writes this week in The Guardian, "but I believe he's only making it worse."

In his frequent tweets about Trump, Fox has called him "crazy," "pathetic" and a "loser." Fox, who served as president of Mexico from 2000 to 2006, also says he views Trump as a "dictator."

He joins a growing number of prominent Mexicans who are speaking out more forcefully against the Republican candidate, and he explained his thinking in an interview with Weekend Edition's Rachel Martin.

Why do you call him a dictator?

We know about dictators in Latin America — these people who have gotten in love with soft talk with audiences like [the late Venezuelan leader] Hugo Chavez did, and once they are in power, they show what they really are. And this I tell to the American people: "Wake up, listen carefully to this false prophet, who could not tolerate this ... that could be a reality tomorrow."

Isn't some of this overheated campaign rhetoric?

We have all followed, especially myself, the electoral process in the United States, and I have never seen something like this. I am absolutely shocked that the Republican Party has let this guy go so far. So I really want American citizens to really consider, is that really the best option that you have?

Your grandfather was born in Ohio and crossed the border in the opposite direction. What motivated him to do this?

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