Even though President Donald Trump repeatedly insisted that Mexico would pay for the new border wall, he never said anything about building it on conquered Mexican land.

According to E&E News, Interior Secretary Ryan Zinke discussed the logistics of building the president’s proposed border wall while attending an event organized by the Public Lands Council this week. He claimed that Trump’s administration has no plans on building the wall on American land because that means they would have to give up the Rio Grande to Mexico.

“The border is complicated, as far as building a physical wall,” Zinke said. “The Rio Grande, what side of the river are you going to put the wall? We’re not going to put it on our side and cede the river to Mexico. And we’re probably not going to put it in the middle of the river.”

Even though Zinke didn’t say how the wall would get built, but if they don’t plan on putting it on the U.S. side of the Rio Grande, then the Mexican side is the only place they can put it.

Zinke also said that the Trump administration will sign a waiver to the Endangered Species Act because they will have to go through jaguar habitats which are now under protection from “destruction of adverse modification.”