US President Donald Trump on Thursday said he would send thousands of National Guard troops to the southern border, amid a widening spat with his Mexican counterpart Enrique Pena Nieto. "If your recent statements are the result of frustration due to domestic policy issues, [due] to your laws or to your Congress, it is to them that you should turn to, not to Mexicans".
The ongoing talks on modernizing NAFTA have also strained ties between the two countries, as well as Canada, the third member of the agreement - though the three countries have recently indicated they are close to reaching a new deal.
Pena Nieto has faced criticism for failing to take a tough line against Trump in the past.
Lopez Obrador said crime rates in US border cities had been falling in recent years, as had the number of Mexicans seeking to cross the border.More news: Oklahoma teachers chalk cars to spread message about needed funding
The front-runner in the race, Andres Manuel Lopez Obrador, said Trump's scheme was political "propaganda" based on misinformation that aimed to stir up "xenophobia" and "racism".
Andres Manuel Lopez Obrador, the sometimes fiery leftist gunning to be Mexico's next president, disputed Trump's anti-migration arguments, saying that crime is actually down in United States border cities, that less Mexicans are crossing the border and that deportations have fallen under Trump.
"The attitude of militarization seems to us like just one more insult that we Mexicans don't deserve", said Ramon Galindo, the state government representative in Ciudad Juarez, across the border from El Paso, Texas.
Jose Antonio Meade, candidate of Pena Nieto's Institutional Revolutionary Party, also attacked the border plan, and independent Margarita Zavala called it a "historic error" and a "hostile act" in a letter addressed to Trump.More news: Gay dating app Grindr to stop sharing HIV status with analytics firms
"The presidential candidates, independently of their natural differences, all of them coincided in rejecting these measures that run counter to good relations between neighbors", Pena Nieto said in a broadcast message.
On Tuesday, the Mexican government asked the United States for clarification on the menaces made by Trump to send the armed forces to the border while the wall that separates his country from Mexico is being lifted.
"As president of all Mexicans, I agree with (their) remarks", he said.More news: Turkey's Erzurum applies to host 2026 Winter Olympics