Acting Homeland Security Secretary Kevin McAleenan couldn’t explain on Sunday morning how President Donald Trump’s proposed tariffs on Mexico wouldn’t just push more people to cross the border due to poor economic conditions caused by said tariffs.

Trump threatened last week to impose a 5 percent tariff on Mexican goods on June 10 if Mexico didn’t stop the flow of border crossings into the US.

“These tariffs are designed to hurt Mexico economically,” CNN reporter Jake Tapper said to McAleenan. “Won’t they just exacerbate the problem? If things go bad economically in Mexico, won’t more people come in and cross the southern border illegally?”

“These crossings into Mexico are happening on a 150-mile stretch of their southern border,” McAleenan responded. “This is a controllable area. We need them to interdict these folks before they make this route all the way to the U.S.”

Tapper then pointed out again that the conditions caused by Trump’s tariffs would incentivize more border crossings and thus make McAleenan’s job harder, a point that McAleenan refused to address.

“Bottom line for me is we need them at the table looking at new strategies that we can aggressively move out on,” the acting DHS secretary said.

The New York Times reported on Saturday that Trump’s economic advisors, such as Jared Kushner and Steven Mnuchin, tried to push back against the President’s proposed tariffs, to no avail.

Watch McAleenan’s interview below: