A pair of Texas Democrats are calling on Joe Biden to seize control of the Texas National Guard and make it comply with a recent Supreme Court order allowing the president’s administration to remove razor wire set up by Texas along the U.S.-Mexico border.

Texas officials, with the support of top Republicans in Congress, are refusing to allow the U.S. Border Patrol to access a park on the banks of the Rio Grande despite the 5-4 ruling by the high court Monday. Texas Gov. Greg Abbott (R) has pushed back and added even more wire fencing, claiming that he has the authority to defend his state from what he called an “invasion” of migrants coming from Mexico.

“Governor Greg Abbott is using the Texas National Guard to obstruct and create chaos at the border,” Rep. Joaquin Castro (D-Texas) wrote in a social media post Tuesday.

“If Abbott is defying yesterday’s Supreme Court ruling ... [Biden] needs to establish sole federal control of the Texas National Guard now.”

Rep. Greg Casar (D-Texas) said that he agreed with Castro on federal control, and accused Abbott of using “political stunts and inflammatory language to advance his own agenda, violating the Constitution and endangering both U.S. citizens and asylum seekers.”

The White House, for the moment, is keeping its distance. National Security adviser John Kirby on Thursday sidestepped questions about Democrats’ calls to federalize the Texas National Guard.

“We talked about this the other day,” Kirby told reporters. “I don’t have any decisions to speak to for the president. I don’t have anything on that.”

The growing border dispute in Texas is taking place as Congress struggles to pass reforms to U.S. immigration law and toughen border policies. Former President Donald Trump and other Republicans are urging their party to reject any deal with Democrats until Trump, the GOP’s likely 2024 presidential nominee, is back in the White House.

On Thursday, Trump fueled the flames by calling on other states to send their National Guard troops to the border to aid Texas, accusing Biden in a post on his website Truth Social of seeking to make it “so that the invasion continues unchecked.”

In Monday’s unsigned order, the Supreme Court lifted a prior federal appeals order barring Border Patrol agents from interfering with the wire except in medical emergencies. Justice Amy Coney Barrett, who was nominated by Trump, joined Chief Justice John Roberts and the three liberals on the court in ruling in favor of the Biden administration. The high court’s order followed the death of three migrants — a woman and two children — who drowned near the disputed area earlier this month.

But Republicans are claiming that Texas has the authority to flout the Supreme Court and the U.S. Constitution, which established that federal courts take precedence over state courts, because of a separate provision of the Constitution that limits the power of states except when engaging in war or being invaded. The rationale, of course, hinges on the semantics of whether illegal crossings by migrants, many of whom are fleeing violence, constitute an invasion.

“Whatever you think of immigration, whatever you think of the influx of unauthorized immigrants along the Texas border, that’s obviously not an invasion as the Founders intended it,” legal scholar Steve Vladeck told CNN on Thursday.

“The real problem with Gov. Abbott’s position here is that it’s basically just a 21st century version of what’s called nullification, of the argument that every state can decide for itself which federal laws are and are not constitutional, which federal rules they are and are not bound by,” he added.

Rep. Veronica Escobar (D-Texas) said, “There is nothing in the Constitution that allows a state to take on a federal role in the way Greg Abbott has.”

Federalizing National Guard troops wouldn’t be unprecedented. In 1957, during the segregation era, President Dwight Eisenhower seized control of the Arkansas National Guard to ensure that a group of Black students, the “Little Rock Nine,” could attend Little Rock Central High School after Arkansas officials refused to do so.

Rep. Pat Fallon (R-Texas) said that Biden would be making “a huge mistake” if he decided to federalize the Texas National Guard.

“The last time any National Guard troops were federalized was under the Eisenhower administration,” Fallon said during an interview with Fox Business.

“If Joe Biden does this, he may go down in history as the Mexican Drug Cartel 9 Million, because almost 9 million people have crossed illegally under his administration,” he added, appearing to cite a figure for the number of border encounters between immigration officials and migrants.