That's the big item out of the NYT's quick interview with the president-elect, who went off on Twitter this morning.
Summed up: Congress and Trump are going to pay for the border wall now with existing legislation, and then try to get Mexico to pay us back. Trump previously said he'll freeze remittances to get Mexico to pay for it. Mexico says that isn't happening, but they're also adapting to Trump's win.
What's new: By adding the cost of the wall to the renegotiation of NAFTA that Trump has promised, he's adding one more potential way to go after them. MIT has estimated the price tag of a full wall at between $27-40 billion.