Sen. Jeff Flake (R-AZ) on Sunday said that “nobody ought to support” President Donald Trump’s proposed wall on the U.S.-Mexico border if the President is referring to a literal physical barrier.

“Why should he go back on this promise, which was very popular among Republicans in places like your state?” CNN’s Dana Bash asked Flake on “State of the Union,” referring to Trump’s pledge to end the Deferred Action for Childhood Arrivals (DACA) program.

“Because it would be the right thing to do,” Flake replied. “Obviously you hope that presidents keep some of their campaign promises and you hope that they ignore others. This is one that he ought to ignore.”

He said young immigrants who were brought to the United States as children and are granted legal status under the DACA program “should not be punished for the sins of their parents.”

“That’s just the basic principle that we ought to follow here,” Flake said.

“If the President says that he will extend the protections for DREAMers but do it in exchange for funding from Congress, from you, for his border wall, would you go along with that compromise?” Bash asked.

“We still really haven’t seen what he means by the wall,” Flake said. “If that’s a metaphor for border security, we can certainly support that, but if he’s talking about a solitary brick-and-mortar 2,000-mile edifice on the border, then no. Nobody ought to support that.”

Asked how he feels about running for reelection in 2018 amid Trump’s incessant criticism, Flake said, “The people in Arizona tend to elect independent-minded, principled senators.”

“I think the voters here expect me to have my own franchise, to represent them, not to be a rubber stamp for the President,” he added. “So I’m quite comfortable being where I am.”