In an interview Wednesday, President Trump doubled down on his campaign promise that he will build a wall along the southern border and Mexico will pay for it.

Trump confirmed that U.S. taxpayer dollars would be used to start the construction, but he said reimbursement from Mexico would follow.

“I’m just telling you there will be a payment," Trump said. "It will be in a form, perhaps a complicated form.

On "America's News HQ" today, Steve Moore, former economic advisor to Trump, explained how Trump could make Mexico pay for the wall.

Moore said one possibility is the creation of an import tariff with a provision that the funds go to pay for the wall.

He acknowledged this wouldn't be his preferred strategy, but it's something Trump could do unilaterally without congressional approval.

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Moore said another option is to institute a border crossing fee whenever a person or vehicle enters the U.S. from Mexico.

"That wouldn't necessarily be a bad way to fund it," Moore said. "It's sort of like a user fee. You're using the border, so therefore you pay for security at the border."

Watch more above, and let us know what you think in the comments.

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