Former President Obama called for comprehensive immigration reform to fix a "dysfunctional" system as the Biden administration grapples with what he called a "heartbreaking" migrant crisis at the southern border. 

Obama, during an interview with ABC's "Good Morning America" that aired Tuesday, said reform to the U.S. immigration system is "something that is long overdue." He added that immigration is a "tough" issue because Americans want to be compassionate but that the U.S. having open borders is  an "unsustainable" idea.

Obama's comments come after more than 14,000 Haitian migrants camped under a bridge in Del Rio, Texas, after a surge in border crossings. 

Secretary of Homeland Security Alejandro Mayorkas admitted Sunday that the vast majority of Haitian migrants who crossed the southern U.S. border in recent weeks have already been released into the United States and it is possible that more will follow them.

So far, approximately 12,400 of the people are having their cases heard by immigration judges, while another 5,000 are being processed by the Department of Homeland Security. Only 3,000 are in detention.

Obama said the situation in Del Rio "is a painful reminder that we don't have this right yet and we've got more work to do." 

"As big-hearted as he is, nobody understands that better than Joe Biden," Obama said. "And the question is now: Are we gonna get serious about dealing with this problem in a systemic way, as opposed to these one-offs where we're constantly reacting to emergencies? And I think that that's something that every American should wanna put an end to."

Obama added that "immigration is tough" and "always has been."

"Immigration is tough. It always has been because, on the one hand, I think we are naturally a people that wants to help others," Obama said. "And we see tragedy and hardship and families that are desperately trying to get here so that their kids are safe, and they're in some cases fleeing violence or catastrophe."

He added: "At the same time, we're a nation state. We have borders. The idea that we can just have open borders is something that ... as a practical matter, is unsustainable."

 White House press secretary Jen Psaki on Monday knocked "Republicans who are standing at the border and giving speeches," though President Biden has yet to travel to the southern border amid the ongoing crisis.

"For all of those Republicans who are standing at the border and giving speeches about how broken the system is, Why don’t you join us and be a part of the solution instead of relying on speeches," Psaki said to reporters during the White House press briefing.

"Because we can work together and get immigration reform passed and make the system work," Psaki continued.

Texas Republican Rep. Ronny Jackson responded to Psaki's comments in a Monday email to Fox News, offering a "solution" of his own to the mounting border crisis.

"Here’s a solution: finish building the wall, fully reimplement the Remain in Mexico policy, and stop undermining our brave border patrol officers at every turn," Jackson said. "President Trump’s successful approach to immigration gave us the most secure border in history, and Joe Biden started undoing that success on day one."

"We don’t have to stand around and wonder what, or rather who, created this crisis," Jackson added. "Joe Biden did this all on his own and is now refusing to carry out the obvious solutions."

Biden has yet to visit the border during his time in office. In fact, it's unclear whether the president has ever visited the border during his decades-long political career. 

Psaki on Monday also stood by the White House's criticisms last week of mounted border agents dealing with the crisis in Del Rio, Texas. Biden previously claimed that the agents had "strapped" migrants, echoing claims from Democrats that migrants were "whipped," but that claim has since been debunked. 

Psaki was asked whether the administration's position on the agents has changed in light of the debunked "whipping" claims. 

"I don't think anyone could look at those photos and think that was appropriate action or behavior or something that should be accepted within our administration," Psaki said. 

"Our reaction to the photos has not changed," she added. 

CNN host Jake Tapper hit critics who spread "patently false" rumors about the mounted Border Patrol agents on the southern border on Sunday's "State of the Union," some of whom were members of the Biden administration.

When a now infamous image of a Border Patrol agent mounted on a horse appearing to be corral migrants with a rope made the rounds on social media last week, critics were quick to accuse the agents of "whipping" Haitian migrants trying to enter the country illegally. More context for the photo revealed, however, that the reins were only used to control their horses. Still, leading Democrats and members of the media pushed ahead with the original story and the Department of Homeland Security launched an investigation into the matter. To some, it sounded as though members of the Biden administration had already made up their minds about the agents.

"I promise you those people will pay," President Biden said. "They will be - an investigation under way now, and there will be consequences. And there will be consequences."

White House press secretary Jen Psaki took the same approach, accusing Border Patrol of "brutal and inappropriate" behavior.

Despite saying he was going to "wait for the facts" in the DHS probe, Homeland Security Secretary Alejandro Mayorkas, also said the images "horrified" Americans. Tapper pressed him on how DHS can "claim" to conduct an independent investigation, considering how the administration has described the images at the border. The CNN host wondered if the agency will conduct the probe "based on the facts, and not based on Twitter outrage."

Mayorkas clarified that what the images "suggest" is what "horrified" Americans, and pledged that the facts in case are going to drive the outcome. 

"But that’s the thing. Some of the initial descriptions of those images were just patently false," Tapper pressed. "There’s now video out there that provides more context. Having seen the video, are you certain that there was actually wrongdoing?"

Mayorkas praised Border Patrol agents as "heroic" and "tireless" and said he was "incredibly proud" to work alongside them, leaving Tapper to wonder whether he shared those same sentiments with Biden.

"The nice words you said about [Border Patrol], you should probably share with President Biden—not just with me today," Tapper said.

Chief White House Spinner Jen Psaki said today that after the ‘horrible and horrific’ photos that came out this week of Border Patrol agents using horses to block Haitian illegals, they would not be allowed to do that any longer:

"I can also convey to you that [DHS Secretary Alejandro Mayorkas] also conveyed to civil rights leaders earlier this morning that we would no longer be using horses in Del Rio," she said.

A DHS spokesperson later said in a statement: "We have ceased the use of the horse patrol in Del Rio temporarily. We'll prioritize other methods for identifying individuals who might be in medical distress."

The revelation comes on the fourth day of controversy related to the false claims that agents used "whips" against Haitian migrants on Sunday – a claim that was initially debunked by Mayorkas and Border Patrol chief Raul Ortiz on Monday, who noted that agents were wielding long reins to control their horses in difficult riverines.

Other Border Patrol sources have noted that agents will spin or twirl their reins in order to move the horse forward as a signal to the horse. So far no images have been presented of migrants being hit by the reins.

However, as the White House condemned the images, by Tuesday Mayorkas had changed his stance.

"I was horrified by what I saw," Mayorkas told CNN. "I'm going to let the investigation run its course. But the pictures that I observed troubled me profoundly. That defies all of the values that we seek to instill in our people."

On Tuesday, Vice President Kamala Harris said she supported an investigation and was "deeply troubled" by the allegations.

With the burgeoning crisis under the so-called ‘migrant bridge’ in Del Rio, Texas, Biden’s DHS Secretary had the gall to claim today that “our borders are not open”:

I am on the ground in Del Rio where I have received an operational briefing and witnessed first-hand the steps being taken to address the recent increase in migrant encounters. 

I first want to thank the United States Border Patrol, led by Chief Raul Ortiz, a native of Del Rio, for responding to this challenging and heart-breaking situation.  I am grateful for the Chief’s extraordinary leadership. 

I also want to welcome, of course, Commissioner Troy Miller, who's been leading the U.S. Customs and Border Protection since January 20 and has been doing an extraordinary job. 

We are in the midst of a pandemic and a critical migration challenge.  We continue to exercise the Centers for Disease Control's Title 42 authority.  Title 42 is not an immigration authority but a public health authority to protect the American public, to protect the communities along the border, and to protect the migrants themselves.

I want to share with you some of the steps we are taking to address the current situation here in Del Rio.  CBP has surged 600 agents, officers, and DHS volunteer force personnel to the Del Rio sector to enhance our operational capabilities.  If additional staff is needed, more will be sent. 

Border Patrol is coordinating with ICE and the U.S. Coast Guard to move individuals from Del Rio to other processing locations—including approximately 3,500 over the last few days and 3,000 today—in order to ensure that migrants are swiftly taken into custody, processed, and removed from the United States consistent with our laws and policies. 

We in DHS are securing additional transportation to accelerate the pace and increase the capacity of removal flights to Haiti and other destinations in the Western Hemisphere.  We are working to increase the capacity of return flights to Haiti and other destinations.  We anticipate at least one to three flights per day.  The Biden Administration is working with source and transit countries in the region to accept individuals who previously resided in those countries.

We are undertaking urgent humanitarian actions with other relevant federal, state, and local partners to reduce crowding and improve conditions for migrants on United States soil.  DHS has already taken a number of steps to ensure the safety and security of individuals as they await processing, including having Border Patrol emergency medical technicians on-hand, and providing water, towels, and portable toilets.  This is all part of an all-of-government and whole-of-community effort.  We have brought in personnel from the Department of Health and Human Services to address medical needs and supplies.  We've also worked with the American Red Cross to bring in supplies and much needed resources to the population.  We have worked with the World Central Kitchen to bring in meals for the migrants.  Not only do we leverage the resources and capabilities of the Department of Homeland Security, we look across the Federal government and in partnership with civil society, local resources, to see what we can do to bring more capabilities to bear to meet the challenge, and that is indeed what we are doing here. 

Finally, the White House has directed appropriate U.S. agencies to work with the Haitian and other regional governments to provide assistance and support to returnees.  The majority of migrants continue to be expelled under CDC’s Title 42 authority.  Those who cannot be expelled under that authority and do not have a legal basis to remain will be placed in expedited removal proceedings.  DHS is conducting regular expulsion and removal flights to Haiti, Mexico, Ecuador, and Northern Triangle countries. 

We are very concerned that Haitians who are taking this irregular migration path are receiving false information that the border is open, or that Temporary Protected Status is available.  I want to make sure that it is known that this is not the way to come to the United States.  That is false information.  Irregular migration poses a serious security risk to the migrants themselves.  Trying to enter the United States illegally is not worth the tragedy, the money, or the effort.  As we have said consistently since we published the Federal Register Notice officially designating Haiti for Temporary Protected Status—or TPS—only Haitians living in the United States before July 29 are eligible for Temporary Protected Status. 

We have reiterated that our borders are not open, and people should not make the dangerous journey.  Individuals and families are subject to border restrictions, including expulsion.  Irregular migration poses a significant threat to the health and welfare of border communities, and to the lives of the migrants themselves, and should not be attempted.  If you come to the United States illegally, you will be returned.  Your journey will not succeed, and you will be endangering your life and your family's lives.  This Administration is committed to developing safe, orderly, and humane pathways for migration, but this is not the way to do it.  Thank you. 

It is my pleasure to introduce Commissioner Troy Miller of the United States Customs and Border Protection.

 Vice President Kamala Harris on Tuesday said she is "deeply troubled" by images from the border showing Border Patrol agents on horseback blocking migrants from entering the U.S. – the latest administration official to join the pile on against agents who are dealing with a colossal migrant surge in Del Rio.

"What I saw depicted about those individuals on horseback treating human beings the way they were, was horrible," Harris told reporters. "And I fully support what is happening right now, which is a thorough investigation into exactly what is going on there. But human beings should never be treated that way. And I'm deeply troubled about it. And I'll also be talking to Secretary [Alejandro] Mayorkas about it today."

Harris was reacting to images of Border Patrol agents in Del Rio, where thousands of Haitians have surged in recent days. Images showed agents on horseback blocking migrants from entering the U.S. and in one case grabbing onto a migrant’s shirt. 

Overwhelmed agents have been working six days a week, and more than 10 hours a day as they deal with the more than 14,000 mostly Haitian migrants that were at one time camped under the international bridge – with reports of tens of thousands more on the way.

As DHS has surged resources, including more agents on horseback, supplies and medical assistance, while also increasing deportation flights, the men and women in green have been attempting to stop migrants – who have traveled through multiple countries before arriving at the border – from coming into U.S. territory.

Some Democrats and media outlets falsely described the agents’ long reins, which they use to control their horses, as "whips." House Speaker Nancy Pelosi condemned what she described as "the inappropriate use of what appear to be whips by Border Patrol officers on horseback to intimidate migrants." 

Mayorkas and Border Patrol Chief Raul Ortiz both said on Monday that they did not see anything wrong with the images, and Mayorkas pointed out agents use long reins to control their horses, not whips, in difficult terrain. Ortiz also noted that agents don't know who are smugglers and who are migrants.

Ortiz said it is important that agents need maintain control of the horse to avoid injuries to both agents and migrants, and said working a horse in a riverine is a very difficult task. 

But the White House took a different view. Press Secretary Jen Psaki said: "I don't think anyone seeing that footage would think it was acceptable or appropriate."

By Tuesday morning, Mayorkas had changed his perspective.

"I was horrified by what I saw," Mayorkas told CNN. "I'm going to let the investigation run its course. But the pictures that I observed troubled me profoundly. That defies all of the values that we seek to instill in our people."