Mexico’s former president recently shared how he thought Donald Trump’s plan to set up a border wall was a “stupid” idea. Felipe Calderon said that Mexico will not be paying a single cent for such a project.

According to Washington Times, Trump said in October 2015 that he would build a wall along the southern border of the United States and have Mexico pay for it. Calderon, who was president of Mexico from 2006 to 2012, had a harsh response to the candidate’s plan.

“We are not going to pay any single cent for such as stupid wall! And it’s going to be completely useless,” Calderon said at the AmCham Egypt for Business Conference earlier in February 2016.

Calderon continued by describing the U.S. as the “first loser” of such a policy. He said that if Trump pretends that shutting the borders to anywhere either for people or trade will add prosperity to the U.S., he is completely crazy.

NBC News wrote that Calderon continued to lambast the Republican presidential contest, saying that it was incredible that the United States had candidates like Trump. He said he means no offense to America, but Donald Trump is ambitious and lacks information. He added that he does not want to say that Trump is ignorant, but only not very well informed.

Among the main focuses of Trump’s campaign revolved around border issues and immigration problems. He particularly targeted Mexico since the day he announced that he was running for the presidency and immediately garnered backlash from the Latino community.

Calderon also frowned upon Trump’s claim that illegal immigration from Mexico is a growing problem, considering how a November report by Pew Research indicated that more Mexicans were leaving the U.S. than entering. Calderon said that fewer Mexicans wish to move to the U.S. A number of huge companies are coming to Mexico, so the youth actually has job opportunities at home. The unemployment rate is about four percent, although Calderon admitted that some local places still offer very low salaries.

An article by CNBC noted that from 2009 to 2014, 1 million Mexicans and their families, including those born in the U.S., left for Mexico. U.S. census data during the same period presented that about 870,000 Mexicans moved to the U.S., which means that there are more Mexicans emigrating from the U.S.

More updates and details on Donald Trump and Felipe Calderon are expected soon.