President Trump told reporters Thursday morning he never expected Mexico to make a direct payment to pay for a border wall, despite a memo from his campaign in 2016 outlining a plan to make Mexico do just that.

"When during the campaign I would say Mexico is going to pay for it, obviously I never said this and I never meant they were going to write out a check, I said they're going to pay for it," Mr. Trump said.

He claimed that increased revenues under the U.S.-Mexico-Canada Agreement, which has not been approved by Congress, would mean Mexico would indirectly pay for the wall. However, any additional revenue resulting from the trade deal in the future couldn't be put toward construction efforts without being allocated by Congress.

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"When I said 'Mexico will pay for the wall' in front of thousands and thousands of people, obviously they're not going to write a check, but they are paying for the wall indirectly many, many times over by the really great trade deal we just made," Mr. Trump continued.

But Mr. Trump's campaign sent a memo to the Washington Post in April 2016 outlining how he would force Mexico to make a one-time payment to pay for the wall. The memo appeared on a since-deleted page on his campaign website.

"It's an easy decision for Mexico: make a one-time payment of $5-10 billion to ensure that $24 billion continues to flow into their country year after year," the memo read.

The Trump campaign laid out "several ways to compel Mexico to pay for the wall." The plan involved threatening on the first day of Mr. Trump's presidency to issue a regulation cutting off remittances to Mexico from immigrants in the U.S.

"On day 3, tell Mexico that if the Mexican government will contribute the funds needed to the United States to pay for the wall, the Trump Administration will not promulgate the final rule, and the regulation will not go into effect," the memo read. The memo also mentioned tariffs, visa cancellations and visa fees as other ways to pressure the Mexican government into paying.

Mr. Trump's insistence that Mexico would pay for the wall was a cornerstone of his campaign. In many rallies, it became part of a call-and-response with attendees, where audience members would respond "Mexico" when Mr. Trump would ask who was going to pay for it.

In his speech announcing his campaign in 2015, Mr. Trump made building the wall a key part of his pitch.

"I will build a great great wall on our southern border and I'll have Mexico pay for that wall," Mr. Trump said.

In an appearance on CBS News' "Face the Nation" in August 2015, Mr. Trump reiterated he would build the wall on Mexico's dime.

"We're building a wall. And it's going to be a great wall. OK? And, by the way, Mexico will pay for it," Mr. Trump said. "This will be a wall with a very big, very beautiful door, because we want the legals to come back into the country."

Mr. Trump continued to say that Mexico would pay for the wall even after he was elected. When meeting with the Finnish president in January 2017, he said "one way or the other, Mexico is going to pay for the wall."

"It may be through reimbursement, but one way or the other, Mexico will pay for the wall," Mr. Trump said.

"Oh, Mexico is going to pay," the president also told CBS News' John Dickerson in an interview in May 2017.

Dickerson followed up, "A hundred percent – the whole thing?"

"A hundred percent," the president replied. "They're going to be happy with it. They'll be very happy to pay."