President Trump has refused to back down on his promise to make Mexico pay for a wall along the United States-Mexico border, prompting a White House trip by Mexican President Peña Nieto to be canceled.

Trump and Nieto decided to call off the planned visit in Washington, DC, after a phone conversation about the proposed U.S.-Mexico border wall and how it would be paid for — in one way or another — by Mexico.

The Washington Post reports:

Tentative plans for Mexican President Enrique Peña Nieto to make his first visit to the White House to meet with President Trump were scuttled this week after a testy call between the two leaders ended in an impasse over Trump’s promised border wall, according to U.S. and Mexican officials. Peña Nieto was eyeing an official trip to Washington this month or in early March, but both countries agreed to call off the plan after Trump would not agree to publicly affirm Mexico’s position that it would not fund construction of a border wall that the Mexican people widely consider offensive, said the officials, who spoke on the condition of anonymity to discuss a confidential conversation.

Since 2015, Trump has promised Americans that a border wall — currently held up in the prototype stage — would be built along the southern border to stop illegal immigration and cartel-driven drug flow into the country.

Mexico, Trump has committed, will somehow end up paying for the border wall, whether that comes in the form of taxing remittances to have illegal aliens from Mexico actually pay for the wall or tariffs on imported goods from Mexico.

Trump’s refusal to back down to Mexico on the border wall has been ongoing during his time as president. Last year, he told Nieto that he would be walking away from a deal with the country unless it included Mexico paying for the wall along the U.S.-Mexico border.

“The fact is, we are both in a little bit of a political bind because I have to have Mexico pay for the wall,” Trump told Peña Nieto, according to a transcript of the call. “I have to. I have been talking about it for a two-year period.”

“If you are going to say that Mexico is not going to pay for the wall, then I do not want to meet with you guys anymore, because I cannot live with that,” Trump continued.

Trump’s wall along the southern border is only expected to cost about $18 billion, a fraction of what American taxpayers have been paying for illegal immigration.

For example, American taxpayers are forced to pay about $116 billion annually for the cost of the estimated 12 to 30 million illegal aliens living across the U.S., as Breitbart News reported. The cost of illegal immigration to American taxpayers has risen by $3 billion since 2013.