President Trump made news late last month when he urged Congress to design a legal immigration system that prioritizes educated foreign workers who can assimilate easily and are qualified for high-skilled jobs.

"It is a basic principle that those seeking to enter a country ought to be able to support themselves financially," the president declared from the dais of the House chamber.

It was the first and last time the president has beseeched lawmakers to consider a "merit-based" immigration system. But the absence of details from the White House has done little to delay critics and proponents from speculating about the economic consequences such a system might bring.

"A merit-based system that is properly designed could be very effective, but I'm concerned that there may be some people around President Trump who really just want to get rid of everything except some high-skilled visas and then make the high-skilled program harder to use," said Tamar Jacoby, president of ImmigrationWorks USA and an adviser to several Republicans on immigration.

"The ultimate upshot of that will mean much less immigration, and the immigration that there is would be so difficult to deal with the bureaucracy that even companies that need the workers would find it easier to move to a different country," she added. "If I'm Microsoft and I can't find enough engineers here, I'm going to move more of my operations overseas."

Trump has pointed to Canada and Australia as countries with immigration models that he hopes the U.S. might emulate. Both countries use points to determine who is eligible for entry, giving those with diplomas and plump résumés more points and therefore a greater chance of being selected. The U.S. operated under a similar system until 1952, when the government stopped imposing literacy tests on immigrants.

Those who favor implementing a system that places an immigrant's employability above his or her family ties say that Americans would see greater economic growth and a reduced reliance on public assistance. Many have pointed to a 2015 report by the conservative Center for Immigration Studies that found that less-educated legal immigrants make "extensive use" of taxpayer-funded federal benefits for housing, food, healthcare and income.

According to the study, three-quarters of households headed by legal immigrants without a high school degree use at least one welfare program, while 64 percent of legal immigrants with a high school diploma also rely on at least one form of federal benefits. Strictly admitting high-skilled immigrants would create wage growth and greater employment opportunities for Americans, merit-based advocates say.

"The big problem is that low-skilled immigration is a labor subsidy which benefits employers by relaxing wage pressure and wage growth and produces a heavy burden on taxpayers," said Federation for American Immigration Reform President Dan Stein. "There simply is no economic rationale for admitting people without the skills and education to really be competitive in our post-industrial information society."

"We're running an immigration program that may have made sense 100 years ago, but makes virtually no sense today," he added.

But Jacoby said the U.S. should favor an immigration system that serves "our American interests," saying that low-skilled migrants and their labor and purchasing power are critical for continued economic growth.

"Right now a third of our visa recipients are family-based and less than 10 percent are employment-based, so I think it would make a lot of sense to reallocate that balance. But if you switch to a system that only lets in those with Ph.D.s and perfect English, and ignores farm workers, every company that farms specialty crops in America would have to move to Mexico or Central America or something else," she said.

"Donald Trump says he's going to build infrastructure through a trillion-dollar investment with no immigrants, I mean good luck," Jacoby added. "That's who works on road crews these days. Americans don't want to work outside on the asphalt in the hot sun."

With a scarcity of details on what the president might want in a comprehensive immigration reform package, the arguments being waged over merit-based immigration have typically boiled down to whether the U.S. should implement a system that concentrates on economic prosperity or one that focuses on the social well-being of Americans and immigrant families.

White House press secretary Sean Spicer said recently that Trump has been discussing that central question "for weeks" with members of Congress, including with Republican Sens. Tom Cotton and David Perdue, who introduced a bill that aims to curb legal immigration substantially and limit visas for family members of immigrants already in the United States.

"He'd like to see additional steps focusing on some of the employment-based green cards and visas. And we're happy to work with him on that," Cotton said this month.