Mexican President Enrique Pena Nieto cancelled a meeting with US President Donald Trump over the latter's promise to build a wall between the two countries, then force Mexico to pay for it.
Trump's take? "Unless Mexico is going to treat the United States fairly, with respect, such a meeting would be fruitless, and I want to go a different route."
The ongoing spat is causing concern on both sides of the border.
TRT World's Tetiana Anderson in Santa Monica, California, spoke to some of the people who might be affected by the wall.