Former Congressman and libertarian icon Ron Paul has some advice for President Trump.

Instead of building a wall along the southern border to keep out illegal immigrants, maybe he should instead try removing the incentives that attract them to the US in the first place - incentives like a relatively easy path to citizenship and easy access to welfare benefits.

After Paul said the shutdown "isn't significant in the scheme of things," Paul's interviewer, Squawk Box's Andrew Ross Sorkin, asked if he supported Trump's border wall, Paul responded that he "doesn't like walls" (though he didn't say outright that he opposes Trump's plans).

"I don't like walls. I'm a libertarian I don't want to wall people in and wall people out." "I don’t want free, open borders either," he continued. "I think you have to remove the incentives for people to come. They come because there's a welfare system here, there's easy access to citizenship its politicized one group wants them here because they think they can get the votes."

Paul said he understands this dynamic thanks to his experience working as a doctor near the border.

"I'm an OBGYN doctor close to the border. People would pop in they'd have a baby then the next day they'd be at the courthouse signing up for welfare benefits."

When asked whether he and his son, Sen. Rand Paul, had discussed this difference in opinion, Paul said that though they talk often, his son doesn't feel like he needs to run all of his political positions by him first.

Watch a clip from the interview below:

Former US Rep. Ron Paul: Border wall unnecessary if US ends incentives from CNBC.