President Donald Trump will sign a bunch of executive orders today over national security issues, including a wall along the border of America and Mexico and policy against sanctuary cities. Trump will visit the Department of Homeland Security (DHS) where he will sign all the orders.

Trump made immigration the cornerstone of his campaign, often talking about a wall along the border and stopping Syrian refugees from entering the country. According to the Associated Press, one person in the administration said the proposals “included a ban on entry to the U.S. for at least 30 days from countries including Iran, Iraq, Libya, Somalia, Sudan and Yemen, though the person cautioned the details could still change.”

The wall, one of the more controversial points of his campaign, may come along due to a 2006 law signed by President George W. Bush. The Secure Fence Act led to building of a fence along Texas, New Mexico, Arizona, and California. The project finished in 2009. But Trump may face complications from a 1970 treaty with Mexico, which states “that structures cannot disrupt the flow of the rivers, which define the U.S.-Mexican border along Texas and 24 miles in Arizona, according to The International Boundary and Water Commission, a joint U.S.-Mexican agency that administers the treaty.”

No one knows yet if the immigration policy will include any action on the Deferred Action for Childhood Arrivals (DACA) program started in 2012, which gives those who came to America as children “temporary protection from deportation.” The Washington Post reported:

Several people familiar with the discussions emphasized that the week’s actions are intended to start fulfilling Trump’s campaign promises on immigration and bring Republicans behind Trump on the issue, one day before he speaks at Thursday’s congressional GOP retreat in Philadelphia. These people spoke on the condition of anonymity because the executive orders were still being finalized.

White House aides said Trump planned to meet Wednesday with several parents of children who were killed by immigrants who are in the country illegally. These activists, who refer to themselves as “angel moms,” were frequently featured during Trump’s campaign rallies and during the Republican National Convention.

The ban could give the administration time to figure out how to properly vet those coming from nations with high Islamic terrorism. Sen. Jeff Sessions (R-AL), Trump’s pick for attorney general, and DHS Secretary John Kelly both said they do not want an outright ban on Muslims. Sessions, though, agreed people from those nations need more vetting. Kelly told his Senate committee that he will “promote ‘tolerance’ and said he didn’t think it was appropriate to target any group of people solely based on religion or ethnic background, including through the development of a registry.”

Kelly also explained to the committee that a “wall might not ‘be built anytime soon.'” He stressed that “security of the border starts 1,500 miles south of the Rio Grande in the jungles of Latin America.”

On the campaign trail, Trump claimed that Mexico would pay for the wall, but Mexican officials said no way. The Government Accountability Office put the price tag at “$6.5 million per mile to build a single-layer fence.” The office then stated that the government will need “an additional $4.2 million per mile for roads and more fencing.”

Another executive order could declare the Muslim Brotherhood a terrorist group. Trump will also consider keeping the CIA’s black sites open. President Barack Obama ordered to close all the sites in 2009. The Washington Post obtained a copy of the order:

The draft, labeled “Detention and Interrogation of Enemy Combatants” notes that the United States has “refrained from exercising certain authorities critical to its defense” in the war on terrorism, including “a halt to all classified interrogations by the Central Intelligence Agency.”

The document stops short of instructing the CIA to rebuild prisons or resume interrogating terrorism suspects, a prospect that is likely to face opposition from an agency that faced criminal investigations and searing criticism after the interrogation program was exposed.

The order calls for a recommendation to the president on whether he should “reinstate a program of high-value alien terrorists to be operated outside the United States and whether such a program should include the use of detention facilities operated by the Central Intelligence Agency.”