With Donald Trump and Ted Cruz each doubling down on the “deport-them-all” approach to illegal immigration ahead of the Super Tuesday primaries, one Washington think tank is warning that deporting 11.3 million people would trigger a recession.

According to a new report from the American Action Forum, the Trump and Cruz plans — each Republican presidential candidate has said all undocumented immigrants in the country must leave the country — would cost between $400 billion to $600 billion over 20 years, would reduce the size of the economy by a recession-level 5.7 percent and would lower the gross domestic product by $1.4 trillion.

Those calculations are based on the federal government maximizing deportations for the next two decades at current funding levels for enforcement officers, courts and transportation — which works out to about 400,000 deportations a year.

Trump has said he’d get the job done in two years, fast-tracking deportations at a pace of more than 15,000 per day — an expedited process that would require a massive expansion of the country’s immigration and deportation process, according to the AAF, a center-right think tank run by former Congressional Budget Office director Doug Holtz-Eakin.

The additional cost to the federal budget would be dwarfed by the $1 trillion the move would cost the U.S. economy, according to the AAF report — a collapse that would feel like the Great Recession all over again.

“The steep decline in the labor force would cause the economy [to] decline sharply. At the end of 2018, the economy would be 5.7 percent smaller than it would be if the government did not remove all undocumented immigrants,” reads the report, released Sunday. “For purposes of comparison, note that the decline in real GDP during the Great Recession was quite similar — 6.3 percent.”

Fully enforcing current immigration law and deporting 11.3 million in only two years, as Trump has proposed, would be, according to the AAF, a “monumental task that would require an unprecedented expansion in U.S. immigration enforcement personnel and infrastructure.”

“I think it’s a process that can take 18 months to two years if properly handled,” the New York billionaire said in September.

Trump repeated during last week’s GOP debate in Houston that if he is elected, “They will go out. They will come back — some will come back, the best, through a process. They have to come back legally. They have to come back through a process, and it may not be a very quick process.”

Trump’s rival for the GOP presidential nomination, Texas Sen. Ted Cruz, has also called for deporting anyone in the country illegally without regard to how long the person has lived in the U.S. Cruz dismissed the Trump plan to let “some” come back as “amnesty.”

Deporting 11.3 million in two years instead of 20 years — even if 20 percent of the undocumented leave the country voluntarily — ramps up costs considerably, according to the AAF.

The nonprofit’s report details what an expedited mass deportation would look like:

• Federal immigration apprehension personnel would increase from 4,800 to almost 90,600.

• In federal detention facilities, bed spaces would have to increase from 34,000 to over 348,800.

• The number of attorneys required to legally process the undocumented would have to increase from 1,430 to over 32,400.

• The U.S. government would have to charter a minimum of 17,300 flights and 30,700 bus trips per year to transport immigrants back to to their country of origin.