Wolf Blitzer: "If you don't get an actual check from the Mexican government for $8 billion or $10 billion or $12 billion, whatever it will cost, how are you going to make them pay for the wall?"
Donald Trump: "I will, and the wall just got ten feet taller; believe me."
https://www.facebook.com/WolfBlitzer/videos/2176736015718690/
Additionally, in a memo to the Washington Post, Trump stated that he would require Mexican government to write a five to ten billion dollar check to pay for the wall.
In the March 31, 2016 memo, Trump declared he would pressure Mexico to decide: “Make a one-time payment of $5 - 10 billion . . . "
https://apps.washingtonpost.com/g/page/politics/memo-explains-how-donald-trump-plans-to-pay-for-border-wall/2007/
