Updated at 5:25 p.m. ET
President Trump said on Twitter Thursday morning that "if Mexico is unwilling to pay for the badly needed wall, then it would be better to cancel the upcoming meeting" with Mexican President Enrique Peña Nieto.
Shortly afterward, news broke that Peña Nieto had done just that. He also took to Twitter and said he would not attend Tuesday's planned visit to Washington, D.C., without giving a reason.
Peña Nieto tweeted that "Mexico reiterates its willingness to work to reach agreements on behalf of both nations," though the canceled visit is widely seen as a sign of escalating tension between the U.S. and Mexico.
Trump signed an executive order Wednesday that moves ahead with his plan to build a wall along the U.S. border with Mexico — a policy he described as one that's in partnership with Mexico and from which both countries will benefit.
But as NPR's Carrie Kahn in Mexico City reports, Mexico's leader released a video later that night in which he forcefully condemned Trump's plan, calling it divisive. "I have repeatedly said, 'Mexico will not pay for a wall,' " Peña Nieto said.
In the video, Peña Nieto had stopped short of canceling his trip, saying he was still waiting to hear the latest from his negotiators in Washington. And as Kahn reports, he was under significant pressure from lawmakers to scrap the visit.
"We will look for a date to schedule something in the future," White House press secretary Sean Spicer told reporters after Peña Nieto canceled. "We will keep the lines of communication open."
Trump later told Republicans gathered at a retreat in Philadelphia that he and Peña Nieto had "agreed to cancel" the meeting. "Unless Mexico is going to treat the United States fairly with respect, such a meeting would be fruitless and I want to go a different route. We have no choice."
Thursday afternoon, Spicer appeared to refine the idea that Mexico would pay for the wall. NPR's Scott Horsley reports:
"[Spicer] said one idea taking shape is to apply a 20 percent tax on imports from Mexico, as well as other countries with which the U.S. has a trade deficit. That would effectively saddle U.S. consumers with a significant portion of the wall's cost, estimated at $15 billion or more.
"Spicer did not offer details about how the import tax would work, but he said it could be adopted as part of comprehensive tax reform."
Sen. Ben Cardin, D-Md., ranking member of the Senate Foreign Relations Committee, said in a statement that Trump is "already causing serious damage to one of our most important relationships in the world."
He said Trump's "divisive rhetoric and antagonistic policies are undermining our deepest values."
A wall along the Mexican border is likely to be expensive, as NPR's Danielle Kurtzleben wrote. There are a number of estimates out there for how much it might cost — and independent experts put that figure at anywhere from $15 billion to $40 billion.
Thursday, Senate Majority Leader Mitch McConnell, R-Ky., and House Speaker Paul Ryan, R-Wis., said they were planning legislation that would designate $12 billion to $15 billion for the project.
There are also significant legal and logistical hurdles to constructing the wall, Danielle notes — and recent polling data suggest only 37 percent of Americans support building it.