Trump said in a media release that he will make the visit at the invitation of Texas Gov. Greg Abbott, a fellow Republican.
"The Biden Administration inherited from me the strongest, safest, and most secure border in U.S history and in mere weeks they turned it into the single worst border crisis in U.S history," Trump said. "It's an unmitigated disaster zone."
The record arrivals of migrant children have tested the Biden administration, with the U.S. government picking up nearly 60,000 children traveling without their parents across the Mexican border from February to May.
President Joe Biden's administration has maintained it followed best practices when it opened 14 emergency intake sites this spring to respond quickly to overcrowding at Customs and Border Protection facilities and said improvements are being made constantly.
They include the addition of virtual case managers to assist staff on the ground to expedite the release of children, and efforts to identify complicated cases or children without relatives or sponsors to move them to licensed facilities.
READ MORE: 'It was heartbreaking': North Carolina lawmaker visits border as crisis impact deepens
The number of children in the shelters has dropped from a high of more than 23,000 to 16,000. Four emergency shelters have closed, while two more are slated to close soon.
But an account from a federal volunteer who spent two weeks in May at the shelter at Fort Bliss Army Base in El Paso, Texas, highlights the desperation and stress of thousands of children held at unlicensed facilities, waiting to reunite with relatives.
Paramedics were called regularly to treat children suffering from panic attacks so severe that their hands would constrict into balls and their bodies would shake.
The outbursts often occurred after other children were taken away to be reunited with families, dashing the hopes of those left behind at the largest emergency shelter set up by the Biden administration to hold minors who had crossed the U.S.-Mexico border alone.
Some had marks on their arms indicating self-harm, and federal volunteers were ordered to keep out scissors, pencils or even toothbrushes that could be used as a weapon. While girls made origami and braided friendship bracelets, a large number of the children spent the day sleeping, the volunteer said. Some had been there nearly two months.
The volunteer spoke to The Associated Press on condition of anonymity because she was not authorized to talk publicly about what she witnessed on the base from May 12 to May 25. She said she was compelled to speak out because of the despair she observed.
Much of what she described mirrored what advocates who visited the shelter recently recounted to The Associated Press and what children there told them.
"What Biden and (Vice President Kamala) Harris have done, and are continuing to do on our border, is a grave and willful dereliction of duty," Trump said.
The former president said the United States has gone from "having border security that was the envy of the world to a lawless border that is now pitied around the world."
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The conditions in the border facilities raise concerns about why it is taking more than a month on average to release the children when most have family in the United States. More staffing has been added since the emergency shelters were opened this spring amid an unprecedented arrival of migrant children, and the flows have subsided.
"I think there is a general consensus that no child should be in these emergency shelters for more than two weeks," said Aaron Reichlin-Melnick, policy counsel for the advocacy group American Immigration Council.
Lawyers and advocates question why most of the children are at unlicensed shelters.
As of May 31, nearly 9,000 children were kept at unlicensed sites, compared with 7,200 at licensed shelters, court filings by the U.S. government said. While the unlicensed facilities were running at near capacity in May, the licensed facilities were only about half full, according to a report filed by the agency tasked with the children's care.
Trump also criticized Biden and Harris for not touring the border or visiting with "the Border Patrol and ICE heroes risking their lives to defend our nation at a time when the White House is doing everything it can to make their job totally impossible."
An official from the Department of Health and Human Services did not comment specifically on the allegations regarding first responders treating children suffering from panic attacks and other concerns about the minors' safety but said the administration was working on expanding indoor recreation space, mental health support, wellness activities and educational services. The official said mental health services and counseling are available to everyone at the emergency facilities.
Releasing children in U.S. custody has become more critical since earlier this month when Abbott directed a state agency to discontinue licenses for facilities sheltering migrant children.
Meanwhile, Biden is sending $26 million in federal funds back to a U.S. Navy shipyard in Virginia. The money had been marked by Trump to pay for the wall along the Mexico border. The Virginian-Pilot reported Monday that the shipyard money is a sliver of the $3.6 billion that Trump had moved from the Department of Defense. The Biden Administration is now sending billions back to a series of military projects. The Norfolk Naval Shipyard in Portsmouth will use the $26 million to address numerous safety violations in one of its buildings.
The U.S. and Mexico have restricted legal border crossings to essential travel since early in the pandemic.
Trump said he hoped his visit will "shine a spotlight" on "these crimes against our nation" and convey his "unshakeable support" for the "incredible people of ICE and Border Patrol."
NOTE: Video is from a previous report.
The Associated Press contributed to this report.