Later Thursday, it was revealed that border officials had adopted a plan to release some families without transferring them to U.S. Customs and Immigration Enforcement, which manages their deportation cases.
The president called on Congress to immediately change what he said were weak US immigration laws, which he blamed on Democrats. U.S. Customs and Border Protection Commissioner Kevin McAleenan said the agency was on track to make 100,000 arrests or denials of entry during the month, up about 30 percent from February and about double the same period past year.
Mr Lopez Obrador wants the United States to fund $10 billion in economic development programs for Mexico and Central America to attack the poverty and violence he says are the root causes of migration.
Nielsen and other U.S. officials say border patrol officers have been overwhelmed by a dramatic increase in asylum seekers, many of them children and families, fleeing violence and economic hardship in El Salvador, Honduras and Guatemala.
The border agency temporarily reassigned several hundred border inspectors to process migrants, provide transportation and perform hospital watches to keep pace.
Closing the US/Mexican border would undoubtedly have a major economic impact on border towns like El Paso, Texas, where US and Mexican citizens cross the border legally every day.
Trump has repeatedly vowed to close the USA border with Mexico during his two years in office.
Trump Dangles Investment To Caribbean Leaders Who Back Venezuela's Guaido
Maduro, whose key allies are Russian Federation and Cuba, says Guaido is a collaborator in a US plot to overthrow his government. Mr Trump's administration called on Mr Maduro to step down and seized billions of dollars' worth of Venezuela's oil assets.
Trump has threatened to close the border before but did not follow through.
McAleenan said, "And within that group - thousands of criminals, smugglers, gang members and public safety threats that we're sworn to protect this country from".
He says it "would be so easy" for Mexico to stop illegal immigration, which would also strike a blow to drug-trafficking. "But they chose not to", Trump said.
Despite Trump's claims, overall, attempts to get across the border into the United States illegally are down substantially from a decade or more ago.
"We are going to help in every way we can".
Lopez Obrador said Mexico is doing its part to fight immigrant smuggling. That is because nearly all of those crossing were single adults from Mexico who were repatriated back to Mexico nearly immediately.
Mr. Trump has threatened to shut off the border before.
The agency makes 'every attempt to coordinate the release of these individuals with NGOs that provide assistance with basic needs, but the heavy influx in recent months has inundated these organizations as well, ' Rodriguez said.