President Donald Trump conceded that “nothing will ever be perfect” as his administration aggressively moves to crack down on illegal immigration in its first 100 days.

In an interview published in The Atlantic on Monday and conducted last week, reporters Ashley Parker and Michael Scherer asked the president what would happen if his administration accidentally got the wrong person, questioning the possibility of deporting a legal resident or an American citizen.

“Let me tell you that nothing will ever be perfect in this world,” he said.

Those comments come days after CNN reported that three US citizen children — including a 4-year-old suffering from metastatic cancer — were deported with their mothers to Honduras by Immigration and Customs Enforcement.

Trump also told The Atlantic that he’s “not involved” in individual deportations when asked “if he was worried that he may have mistakenly deported innocent people.”

“You know, I’m not involved in that. I have many people, many layers of people that do that,” Trump told The Atlantic.

Trump continued, “I would say they are all extremely tough, dangerous people. I would say that. And, don’t forget, they came in the country illegally.”

Trump’s comments come as the White House is highlighting his efforts to secure the border on Monday as part of its messaging about the president’s first 100 days.

Immigration czar Tom Homan and press secretary Karoline Leavitt will brief reporters later this morning, and the White House North Lawn has been set up featuring images of illegal immigrants who have been arrested.

But public opinion on Trump’s handling of immigration, a signature issue for the president, has waned in recent months. Around 45% of Americans approve of his immigration efforts, according to a new CNN poll conducted by SSRS, down six points from March.