Eric Trump on Wednesday defended his father's stance on immigration as one that "develops" over time, and rejected the idea that Donald Trump has flip-flopped.

"Honestly, I don't think it's flip-flopping at all," Trump said of his father on CNBC. "His message has always been very clear since the beginning of the campaign: It's America first."

When questioned about Trump's comments to NBC News' Chuck Todd last August that illegal immigrants all "have to go," Eric Trump said his father's plans have been evolving.

"I think it develops. And I think he's going to come out and speak, you know, very, very specifically about it. He has a couple immigration speeches coming up, as you know very well," he said.

"But again, his message is America first. He will build a wall. Believe me. I mean, he will build a wall," Eric Trump added.

In an interview with Fox News' Sean Hannity Tuesday night, Trump indicated he's open to "softening" in his hardline plan to deport all 11 million illegal immigrants, but wasn't more specific.