In a string of Monday morning tweets about the caravan of Honduran migrants currently in Mexico, President Trump stated the United States will begin cutting off foreign aid to Guatemala, Honduras and El Salvador.

"Sadly, it looks like Mexico’s Police and Military are unable to stop the Caravan heading to the Southern Border of the United States. Criminals and unknown Middle Easterners are mixed in. I have alerted Border Patrol and Military that this is a National Emergy. Must change laws! ... Guatemala, Honduras and El Salvador were not able to do the job of stopping people from leaving their country and coming illegally to the U.S. We will now begin cutting off, or substantially reducing, the massive foreign aid routinely given to them."

The big picture: Trump has amplified his warnings about illegal immigration in recent days as part of a last-minute push to energize his base before next month's midterm elections. In addition to declaring that the caravan was instigated by Democrats, Trump has now claimed — also without evidence — that "Middle Easterners are mixed in" with the Central American migrants.

Critics argue Trump’s approach would over the long-term actually increase immigration from the three countries, which are struggling with high rates of poverty and violent crime. Incoming Mexican President Andres Manuel Lopez Obrador has suggested a U.S.-Mexico-Canada agreement to invest in Central America in order to address the root causes of immigration.

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