Apparently not content with building a wall, Donald Trump has reportedly threatened Mexican President Enrique Pena Nieto with an invasion to stop the "bad hombres" - unless the Mexicans do more to control them.
"You have a bunch of bad hombres down there," Mr Trump said to the Mexican president, according to an excerpt of a transcript of the conversation obtained by The Associated Press.
"You aren't doing enough to stop them. I think your military is scared. Our military isn't, so I just might send them down to take care of it."
The call between the two presidents was intended to patch up the relationship between the two countries, after Mexican outrage over Mr Trump's call to build a wall and make Mexico pay for it.
However, The Associated Press says their conversation deteriorated, leading to Mr Trump's alleged outburst.
It's not the first time the US President has suggested starting an armed conflict with Mexico.
During the Republican primary race, Mr Trump implied that fear of the US military would force Mexico into complying with his demands.
"When I rejuvenate our military, Mexico's not going to be playing with us with war, that I can tell you. Mexico isn't playing with us with war," he told MSNBC.
However, Mexico's foreign relations department has denied Mr Trump's comments during the call occurred, saying it "is based on absolute falsehoods."
"The assertions that you make about said conversation do not correspond to the reality of it," their statement said.
"The tone was constructive and it was agreed by the presidents to continue working and that the teams will continue to meet frequently to construct an agreement that is positive for Mexico and for the United States."