President Trump invoked the Aliens Enemies Act (AEA) of 1798 on Saturday, fulfilling a campaign promise and GOP party platform point by initiating a concerted effort to remove Venezuelan undocumented immigrants believed to be members of the Tren de Aragua gang, a newly designated Foreign Terrorist Organization. 

Trump has ordered Attorney General Pam Bondi to provide a copy of the invocation to the Supreme Court Chief Justice, all governors in addition to the highest-ranking judicial officer for every state and territory in the United States.

“I proclaim that all Venezuelan citizens 14 years of age or older who are members of TdA [Tren de Aragua], are within the United States, and are not actually naturalized or lawful permanent residents of the United States are liable to be apprehended, restrained, secured, and removed as Alien Enemies,” Trump wrote in the proclamation, which grants Bondi and Secretary of Homeland Security Kristi Noem, the authority to enforce deportation measures.

The president’s move comes hours after a judge temporarily blocked the removal of 5 Venezuelans who the Trump administration says are members of Tren de Aragua. 

The Justice Department has argued the individuals should be removed under the Aliens Enemies Act although they were detained by immigration officials prior to President Trump’s decision to invoke the act. 

U.S. District Judge James Boasberg is presiding over a Saturday emergency hearing to decide if the administration will have to postpone all potential deportations of individuals expected to be repatriated under the Saturday proclamation for a period of two weeks.

The AEA was last invoked under former President Franklin D. Roosevelt during World War II to detain people of Italian, German and Japanese descent.

”The law is best known for its role in Japanese internment, a shameful part of U.S. history for which Congress, presidents, and the courts have apologized,” according to the Brennan Center for Justice.

It is the last remaining pillar of the four Alien and Sedition acts. The three others were either repealed or have expired.

The Alien and Enemies Act is also only applicable under the conditions of war, which has not yet been declared by Congress, according to the Brennan Center.