Memos released Tuesday by the Department of Homeland Security direct agency employees to begin immediately implementing President Donald Trump’s executive orders on immigration and border security.

One of the memos calls for the immediate construction of a wall along the Mexican border.

The other memo declares that President Barack Obama’s executive amnesty program, known as Deferred Action for Childhood Arrivals (DACA), is not to be affected by Trump’s executive orders.

The two memos were signed Monday.

On the campaign trail, Trump pledged to get rid of Obama’s amnesty for illegal immigrants who were brought to the U.S. as children. He has yet to fulfill this goal.

“DACA is a very, very difficult subject for me,” the president said during a press conference last week. “It’s one of the most difficult subjects I have because you have these incredible kids.”

More than 750,000 illegal immigrants have received protection from deportation, work permits, a Social Security number and access to welfare since the implementation of DACA in 2012. The memos released Tuesday do fulfill several of Trump’s other campaign promises.

One of the two memos states, “A wall along the southern border is necessary to deter and prevent the illegal entry of aliens and is a critical component of the President’s overall border security strategy.” The memo orders Customs and Border Protection (CBP) to use materials originating in the U.S. to “immediately begin planning, design, construction and maintenance of a wall, including the attendant lighting, technology (including sensors), as well as patrol and access roads, along the land border with Mexico in accordance with existing law.”

The memos order the hiring of an additional 10,000 ICE officers and 5,000 CBP officers. They also get rid of an Obama administration program which forced ICE to focus on deporting only the most serious of criminals, and reinstate the 287(g) program which allows for local and state law enforcement officials to enforce federal immigration law.