President Donald Trump compared his border wall to the invention of the wheel on Thursday, saying wheels are effective and still commonly used in modern times.

He said even the "really expensive" cars that the Secret Service uses have wheels.

Trump made the remarks at a roundtable with lawmakers and local officials in McAllen, Texas, amid a government shutdown over funding for the border wall.

President Donald Trump drew a bizarre analogy during his trip to the border in McAllen, Texas, on Thursday, likening a border wall to the ancient invention of the wheel and saying wheels are effective and still commonly used in modern times.

"They say a wall is medieval. Well, a wheel is older than a wall," Trump said, though the earliest known border wall is actually thousands of years older than the wheel. "And I looked, and every single car out there, even the really expensive ones that the Secret Service uses — and believe me they are expensive — I said, 'Do they all have wheels?' 'Yes.' 'Oh. I thought it was medieval.'"

He continued: "The wheel is older than the wall. You know that? There are some things that work. A wheel works and a wall works."

Trump made the trip down to the border amid a weekslong government shutdown that shows few signs of stopping anytime soon. The shutdown was caused by a dispute over $5.7 billion in funding that Trump has demanded to construct more than 200 miles of border wall, which Democrats have refused to approve.

In McAllen, Trump participated in a roundtable with lawmakers and local officials who commended him for calling the situation along the border a "crisis" and holding firm on his demands that Congress supply billions for the wall.

Read more: THE TRUTH ABOUT THE BORDER CRISIS: Experts say there is no security crisis, but there is a simple way to fix immigration — and it's not a wall

President Donald Trump speaks as he tours the US-Mexico border on January 10, 2019, in McAllen, Texas. Associated Press/Evan Vucci

During Trump's opening remarks, he lambasted congressional Democrats for refusing to submit to his demands and said they would lose the fight because a wall is "common sense."

"The government is shut down because democrats will not fund border security," he said. "Their open-borders agenda threatens all American families, including millions of legal immigrants throughout our nation."

But Trump has faced criticism in recent weeks for continually calling the state of the border a "crisis" that threatens the lives of Americans.

In a rebuttal to Trump's televised Oval Office address on Tuesday, top Democrats Nancy Pelosi and Chuck Schumer denounced Trump for stoking fear about the migrants who cross the US-Mexico border, many of whom are families with young children seeking asylum.

"Sadly, much of what we have heard from President Trump throughout this senseless shutdown has been full of misinformation and even malice," Pelosi said. "The President has chosen fear."