President-elect Donald Trump has vowed to launch the "largest deportation operation in American history" to address the issue of illegal immigration once he takes office, though the details and true scope of his plan have not yet been fully revealed.

To claim the historical record for the most deportations during a presidential term, however, Trump will need to surpass a seemingly unlikely rival in that regard -- former President Barack Obama, according to the Independent.

Indeed, federal records show that Obama, previously derided by his leftist critics as the "deporter-in-chief," removed or returned more illegal immigrants in each of his two terms as president than Trump did in his first term in office.

Obama holds record for most deportations

First, it must be established how many illegal migrants currently reside in the U.S., but that number varies from around 11 million, according to the Department of Homeland Security and Pew Research, to as many as 13-14 million, per the Center for Immigration Studies, and there are some who suggest the real number could be two to three times higher than those estimates.

Then, it must be determined what constitutes deportation, which generally includes involuntary court-ordered "removals" and the more voluntary "returns" without an order, but typically doesn't include automatic expulsions or turnbacks at the border.

With those metrics in place, the Independent reviewed monthly DHS enforcement statistics and found that in terms of removal orders under the last three presidents, former President Obama had the most at around 1.57 million for his first term and 1.49 million in his second term.

That surpasses the roughly 1.2 million removals ordered during former President Trump's first term, and far exceeds the approximately 650,000 removal orders under President Joe Biden.

When the more voluntary "returns" and self-deportations are factored in, Obama retains his lead with around 2.2 million over his eight years compared to about 600,000 for Trump, bringing their combined repatriation numbers up to more than 5 million for Obama and about 2 million for Trump.

Trump vows to launch "largest deportation program in American history"

If ever there were an incoming president and administration who seem eager to accept the challenge of achieving the most deportations of illegal migrants in U.S. history, it would be President-elect Trump and his "Border Czar" nominee, former Acting Immigration and Customs Enforcement Director Tom Homan, according to ABC News.

Trump spoke repeatedly on the campaign trail about his intent to dramatically reduce the number of illegal migrants in the U.S., and vowed at his Madison Square Garden rally, "On Day 1, I will launch the largest deportation program in American history to get the criminals out."

He has also indicated that he is strongly considering employing unspecified "military assets" as part of the deportation program, but there are few details of how the military might be used and likely legal obstacles to overcome first to do so.

To effectuate his plan for mass deportations, Trump tapped Homan, who has been decidedly straightforward and unapologetic about his aims to deport all illegal migrants with criminal records or who pose national security threats, including by deporting their entire families along with them, if need be.

What Trump must do to earn "deporter-in-chief" title

If President-elect Trump is to make good on his vow to conduct the "largest deportation program" with the most deportations in U.S. history, he will have his work cut out for him to eclipse the current unlikely record-holder in that regard, former President Obama.

That said, if Trump can oversee the repatriation of around 3 million illegal migrants over the next four years, either through court-ordered removals or policies that encourage voluntary returns, he will be able to rightly claim the "deporter-in-chief" mantle from Obama's shoulders.