White House, campaign respond to backlash over Biden's 'illegal' comment

President Joe Biden disappointed some Democrats and immigration activists when he used the term "illegal" at the State of the Union when referring to an undocumented migrant accused of killing 22-year-old nursing student Laken Riley.

Now, the administration and his campaign are weighing in on the off-script moment.

White House communications director Ben LaBolt told ABC News White House Correspondent Karen Travers that when Biden said that, he was reacting to language from an interjecting lawmaker.

"In terms of that particular moment, he was responding to language that was used in the House chamber," LaBolt said when asked whether Biden regretted using that term, considered an offensive and outdated way of referring to undocumented immigrants.

"He wanted to speak directly to the parents of Laken Riley, as somebody who lost a child and speaks and thinks about that on a continual basis and knows what they went through," LaBolt added.

"And you heard him talk more broadly about how he thinks about immigrants in this country," he continued. "The fact that he wouldn't use language like Donald Trump has used, calling them vermin, poisoning the blood of our country, really lifting them up and he respects them as human beings. But also as somebody who supports a bipartisan solution to what's happening at the border."

Biden, too, was asked if he regretted using that language as he was on his way to a campaign event in Philadelphia on Friday afternoon.

"Well, I probably shouldn't -- I don't re-- technically he's not supposed to be here," Biden told the reporter, stopping and starting throughout his answer.

The moment under scrutiny came about halfway through Thursday's address as he turned to talking about immigration and criticizing Republicans for tanking a bipartisan border deal.

Republican Rep. Marjorie Taylor Greene of Georgia -- a vocal Biden critic -- called out from the audience: "What about Laken Riley?"

A back-and-forth between them ensued.

"Laken Riley, an innocent young woman who was killed," Biden started before Greene yelled out, "By an illegal."

"By an illegal. That's right," Biden repeated before expressing his condolences to her family: "To her parents, I say, my heart goes out to you."

The National Immigration Center said it was "shocked" to hear Biden use that term. Rep. Chuy García, D-Ill., said as an immigrant he was "extremely disappointed" to hear it, a sentiment echoed by some other Democratic lawmakers.

LaBolt said he was not aware of any outreach by President Biden or senior White House aides to Democratic lawmakers who have been publicly critical of him for using that term.

Vice President Kamala Harris when asked by ABC News Chief White House Correspondent Mary Bruce if she was comfortable with the language attributed it to a "chaotic" scene, but said Biden was still able to empathize with Riley's family and make his broader pitch on the need to fix the immigration system.

Biden campaign co-chair Mitch Landrieu told CNN earlier Friday Biden "probably should've used a different word" and called it a "small mistake."

Campaign aides, in a testy response to the stir caused by Biden's use of the term "illegal," also sought to stress how different his view on immigration is compared to that of many in the Republican Party, including his rival Donald Trump.

"Oh, yeah, look, I know it may have been difficult to hear over the incessant heckling of Marjorie Taylor Greene last night, but we should be very clear about what the president was saying when it comes to fixing our broken system and in rejecting the cruelty in the equal extremism, it's been pushed by people like Donald Trump and Marjorie Taylor Greene, who are actually just trying to demonize immigrants in an attempt to score political points," Michael Tyler, the campaign's communications director, told a reporter who asked if Biden's remark could hurt his outreach to Latinos.

Tyler accused Trump and Greene of "using immigrants as their primary political punching ban."

ABC News' Molly Nagle, Libby Cathey and Gabrielle Abdul-Hakim contributed to this report.