Jeff Flake is pushing back hard against the Trump administration’s plans to limit legal immigration.

President Trump has vowed to protect an estimated 800,000 so-called “Dreamers” from deportation before provisions from the Deferred Action for Childhood Arrivals program expire in March. But he’s also calling for changes to legal immigration that are controversial with both parties.

On the Senate floor on Tuesday, the outgoing Arizona GOP senator derided the idea, calling it “short-sighted” and saying it would do more harm than good.

“Now some have appeared to seize on this to put forth an agenda to limit the future flow of legal immigration. Before this idea gains any steam, we have to debate and discuss its enormous impact on our economy," Flake said.

Flake said the White House proposals to put limits on legal immigration would make a huge dent in an aging future workforce, while reducing overall economic growth in the U.S. by 12.5 percent by the year 2045.