Amid a political earthquake in Washington following the sudden firing of Secretary of State Rex Tillerson, President Trump arrived in California Tuesday where he reviewed several design prototypes for his proposed wall along the U.S.-Mexico border.
"The border wall is truly our first line of defense," Trump said in remarks after a briefing with officials from Customs and Border Patrol and U.S. Immigration and Customs Enforcement. "The wall will save hundreds of billions of dollars, many, many times what it's going to cost."
The president's visit is his first to the country's most populous state since taking office, and comes just one week after his Department of Justice announced its plan to sue California over "obstructing federal immigration enforcement efforts."
Ahead of his arrival, the president tweeted that "thousands of dangerous, violent criminal aliens are released" as a result of California's immigration sanctuary policies.
Standing alongside one of the prototypes, Trump said tall walls were needed to keep out “incredible climbers.”
“Getting over the top is easy. These are like professional mountain climbers, these are incredible climbers,” Trump said. “They can't climb some of these walls, some of them they can.”
On Monday California's governor, Democrat Jerry Brown, shared on Twitter a letter he wrote to the president, saying his state "thrives because we welcome immigrants and innovators across from across the globe."
"You see in California we are focusing on bridges, not walls," Brown said. "After you've examined your wall prototypes on the border, I invite you to head north to the Central Valley -- the heart of California. Here in cities like Fresno and Madera more than a dozen bridges and viaducts are being built for the nation's first and only High-Speed Rail line."
Trump responded to the criticism from Brown, accusing him of making residents less safe over sanctuary city policies and sky-high taxes.
“I think the governor's doing a terrible job running the state of California,” Trump said. “I have property in California I will say, I don't speak too much about my property any more. The taxes are way, way out of whack and people are going to start to move pretty soon.”
Construction of the eight wall prototypes in the San Diego area were completed in October of last year. Six companies were chosen to build eight sample walls -- four made of concrete and four of other materials -- according to U.S. Customs and Border Protection.
The White House has called for $18 billion in funding for the wall's construction, but that demand has remained in limbo after the administration sought to pair it with a deal to grant legal status to recipients of the Deferred Action for Childhood Arrivals, or DACA, program.
Following the president's tour of the wall designs, he will deliver remarks to troops stationed at Marine Corps Air Station Miramar. In the evening, Trump will attend a GOP fundraiser in Beverly Hills.
ABC's Geneva Sands contributed reporting to this story.