(CNN) Incoming White House acting-chief of staff Mick Mulvaney once called President Donald Trump's views on a border wall and immigration "simplistic" and "absurd and almost childish."
A physical barrier would not stop undocumented immigrants from crossing the Mexican border and ranchers at the border say they don't need a fence, Mulvaney said in a 2015 interview uncovered by KFile.
As Trump's man in charge at the White House, however, Mulvaney would be tasked with leading the administration's push to build a wall along the US-Mexico border.
"Donald Trump says, build a wall. Deport all illegal immigrants. Rules are rules. You either play and stay or you cheat and you get deported. What challenges does this plan pose?" Patti Mercer asked in the August 25, 2015, interview on WRHI radio in South Carolina.
"A bunch," Mulvaney responded.
"The fence doesn't solve the problem. Is it necessary to have one, sure? Would it help? Sure. But to just say build the darn fence and have that be the end of an immigration discussion is absurd and almost childish for someone running for president to take that simplistic of [a] view," Mulvaney added, without making a distinction between a fence or wall.
KFile uncovered the comments as a government shutdown looms over funding for Trump's border wall. "Shutdown today if Democrats do not vote for Border Security!" Trump tweeted Friday.
A spokeswoman for Mulvaney, nor the White House returned a request for comment.