President Joe Biden appeared to be caught off guard during a recent interview when a reporter suggested that "not one" migrant child separated from their families under the Trump administration has been reunited with their parents amid the ongoing immigration crisis.

What happened?

During the interview that aired Friday, NBC "Today" reporter Craig Melvin reminded the president of a campaign pledge he made last year to reunite with their parents migrant children who had reportedly been separated from their families under the Trump administration.

The president, in early February, signed an executive order "to launch a long-awaited task force to reunite families separated at the border under the Trump administration."

But Melvin then claimed that based on NBC News's reporting, "not one child" has been reunited. Axios similarly reported early this month that "not one of the hundreds of migrant families" had been reunited.

"I don't think that's true, but that could be," Biden responded to the charge, adding, "The thing is, we don't know yet where those kids are."

"We're trying like hell to figure out what happened," he continued. "It's almost like being a sleuth and we're still continuing to try like hell to find out where they are."

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What else?

Since the start of Biden's presidency, the problem of managing unaccompanied migrant children has only been exacerbated as an unprecedented number of migrants — many of them children without their parents or other guardians — have surged into the country in anticipation of lenient treatment from the Biden administration.

But Biden assured, "What we have done is united children with their families as they've come across the border."

He told Melvin that the number of migrant children being held in such facilities has gone down "dramatically" of late, but failed to provide any specific number to back up his claim.

The president's comments are troubling, to say the least, given that thousands of unaccompanied minors were reportedly being held in cramped, cage-like Border Patrol facilities in recent weeks for longer than is legally permitted.

Anything else?

Elsewhere in the interview, rather than owning up to his administration's failures, Biden blamed former President Donald Trump's administration for the crisis.

"The two departments that didn't give us access to virtually anything were the immigration and the Defense Department," Biden said, adding that his aides were unaware of how "considerably" understaffed the federal agencies were due to a delayed transition.

"They didn't have beds," he said. "They didn't plan for the overflow."