After Donald Trump met with Mexican President Enrique Peña Nieto on Wednesday, he claimed at a press conference that the two men had discussed the wall Trump has proclaimed he will build on the U.S./Mexico border, but not Trump’s oft-repeated claim that he would make Mexico pay for it. A reporter had questioned Trump whether the two men had discussed who would pay for the wall; Trump replied, "Who pays for the wall? We didn't discuss. We did discuss the wall. We didn't discuss payment of the wall. That'll be for a later date."

Hours later, Nieto issued a denial of Trump’s claim, tweeting: “At the start of the conversation with Donald Trump, I made it clear that Mexico will not pay for the wall.”

In addition, although Jason Miller, Trump's senior communications adviser, responded to Nieto’s tweet that the meeting was "the first part of the discussion and a relationship builder … It was not a negotiation, and that would have been inappropriate. It is unsurprising that they hold two different views on this issue, and we look forward to continuing the conversation," later in the day, the Mexican Foreign Ministry fired back:

“At the start of the conversation with Donald Trump, I made it clear that Mexico will not pay for the wall.”

Mexican President Enrique Peña Nieto

Why Nieto chose to wait hours to respond to Trump’s claim is anyone’s guess; he was present at the news conference when Trump made his claim. Nieto told CNN's Fareed Zakaria in July "there is no way that Mexico can pay (for) a wall like that."

The two men also differed over NAFTA; Nieto lauded NAFTA, pointing out that over six million US jobs rely on exports to Mexico. He asserted, "I don't think that commerce must be considered a zero sum game, so that only one wins and the other one loses.” Trump countered that the "tremendous outflow" of jobs from the United States into Mexico had to stop, arguing that NAFTA benefited Mexico more than the U.S.