Donald Trump's comments about immigration and Muslims are making him among the most popular and most hated in the GOP presidential race, to the point of people refusing to mince words regarding his policies.

Former president Felipe Calderon, for instance, shared tough words when asked about Trump's plan to build a border wall with funds from Mexico.

Calderon told NBC, "We are not going to pay any single cent for such a stupid wall! And it's going to be completely useless."

He also pointed out that the ludicrous notion of an "admirable society" like the US allowing people like Trump to run in the presidential race. The former Mexican president said, "No offense, no offense to America. So Donald Trump ... is ambitious but not exactly very well-informed man, I don't want to say ignorant, but he is not very well informed."

His heat with the business mogul is in regards to the border issues and immigration policies that Trump has centered his campaign around, with comments like Mexico sending "rapists" and "criminals" to the US. Politico noted that in June, Trump said at his campaign launch that Mexicans are "bringing drugs. They're bringing crime. They're rapists. And some, I assume, are good people."

Understandably, these comments set off condemnation from the Latino community -- including the Latino Republicans. Trump's often racist remarks also led to severed ties between himself and other business relationships, including that of NBC's.

Calderon also added that Trump's policy of closing borders is unthinkable in international relations matters. He said that "the first loser of such a policy would be the United States -- If this guy pretends that closing the borders to anywhere either for trade [or] for people is going to provide prosperity to the United States, he is completely crazy."

Besides, it is wrong for Trump to assume that the influx of immigrants come from Mexico. News Max noted that the opposite is actually true, as younger generations are looking into emigrating back to their home country rather than staying in the US. In fact, the Mexican labor force in the US has been declining steadily.

Among the things Calderon pointed out is that the Mexicans in the US will have the same opportunities in their own country, noting that "They don't want to go; they can work for a motor company [that's] not in Detroit, I am sorry to say they are working for a motor company in Hermosillo and Toluca, so Mazda is coming to Mexico, Honda is coming to Mexico. Those kids have jobs in that industry in Mexico."