Katrina Pierson, a spokeswoman for GOP front-runner Donald Trump's presidential campaign, said Wednesday that she can't take Facebook CEO Mark Zuckerberg seriously after the tech billionaire made a thinly-veiled reference to her candidate's positions.

"Self-righteousness isn't very proactive: We can talk about taxes, we can talk about jobs and even immigration, but that doesn't really put food on the table and save lives," she told CNBC's "Squawk on the Street."

"I think I'll take Mark Zuckerberg seriously when he gives up all of his private security, moves out of his posh neighborhood and comes live in a modest neighborhood near a border town, and then I'm sure his attitude would change," she added.

At Facebook's F8 developer conference on Tuesday, Zuckerberg spoke out against those seeking to build walls — physical and digital.

"As I look around and I travel around the world, I'm starting to see people and nations turning inward, against this idea of a connected world and a global community," he said. "I hear fearful voices calling for building walls and distancing people they label as others. For blocking free expression, for slowing immigration, reducing trade, and in some cases around the world even cutting access to the internet."