President-elect Donald Trump On Monday, he confirmed that he would declare a national emergency to fulfill his campaign promise of mass deportations of migrants living in the US without legal permission.

Overnight, Trump responded to a social media post by Tom Fitton of Judicial Watch, who said earlier this month that there were reports that the incoming administration was preparing such a statement and was using “military assets” to deport migrants.

“TRUE!!!” trump card he wrote.

Trump has pledged to begin mass deportations as soon as he takes office.

“On Day 1, I will launch the largest deportation program in American history to get criminals out,” he said during a rally at Madison Square Garden in the final days of the presidential race. “I will save every town and city that has been invaded and conquered, and we will put these vicious, bloodthirsty criminals in jail, then get the hell out of our country as quickly as possible.”

Already, he has appealed to some immigration partisans to serve in key Cabinet posts. South Dakota Gov. Kristi Noem has been tapped to serve as secretary of homeland security, pending Senate confirmation. Former US actor Immigration and the director of the Customs Service, Tom Homan, was called the “border czar.”

Homan has previously discussed his vision for mass deportations, saying they would first focus on deporting criminals and threats to national security. He did not rule out deporting families together.

On Monday, Homan told Fox News’ “America Reports” that he was heading to Mar-a-Lago “this week to put the finishing touches on the plan.”

Homan reiterated his plan to “take the handcuffs off ICE” and step up arrests, though he noted he would need more resources to pull it off and said there were “a lot of what-ifs.”

“So, I’ve been asked a thousand times, how many people can you eliminate in the first year? Well, how many agents do I have?” he said. “We can bring back rehired agents, bring the retired ones back and rehire them. How many buses do I have? How much money do I have for airplanes? Not? Can DOD assist? Because the DOD can take a lot off our plate. There’s a lot of what ifs…”

Throughout the campaign, Trump promised to mobilize the National Guard to help with the deportation effort. expert he told ABC News such a move would mark a fundamental shift for the military, which normally does not involve itself in domestic law enforcement matters.

At times, Trump has gone further, suggesting that thousands of overseas troops be moved to the US-Mexico border.

There are an estimated 11 million unauthorized migrants living in the US without legal immigration status. Removing them could cost billions of dollars a year, according to estimates by the American Immigration Council.

In addition, mass deportations could have a wider economic impact, leading to lost tax revenue and labor shortages.

ABC News Chief Global Affairs Correspondent Martha Raddatz recently reported of California on the impact Trump’s immigration and mass deportation plans could have on the US agricultural industry.

“If you took away my labor, you wouldn’t eat. If you go into the San Joaquin Valley and start doing what you say, it’s over. The country will stop, literally stop because the food system will not move. “, said Manuel Cunha Jr., president of the Nice Farmers’ League.

-ABC News’ Armando Garcia contributed to this report.