WASHINGTON (AP) — The Trump administration is considering bringing on a “border” or “immigration czar” to coordinate the president’s immigration policies across various federal agencies, according to three people familiar with the discussions.

President Donald Trump is weighing two potential candidates for the post: Former Kansas Secretary of State Kris Kobach and former Virginia Attorney General Ken Cuccinelli — two far-right conservatives with strong views on immigration, according to the people, who spoke to The Associated Press on condition of anonymity because they were not authorized to discuss the conversations publicly.

The discussion comes as Trump is threatening to close the southern border as soon as this week if Mexico does not completely halt illegal immigration to the U.S.

White House press aides, Kobach and Cuccinelli did not immediately respond to requests for comment Monday. Kobach previously served as vice chair of the president’s short-lived election fraud commission, which was disbanded after finding little evidence of widespread fraud.

Trump’s focus on immigration had touched on numerous government agencies, including the departments of Homeland Security, Health and Human Services, Defense and Justice. And not all of those departments are always on the same page.

One of the most glaring examples came last summer, when former Attorney General Jeff Sessions instituted a “zero tolerance” policy at the border that caused a spike in the number of migrant children separated from their families.

The separated children were placed in HHS custody, but there was no tracking system in place to link parents with their children until a federal judge ordered one, causing widespread fear and concern about whether families would ever see each other again. Homeland Security also has to coordinate with the Pentagon on space to detain migrants as well as on wall funding.

It has yet to be decided whether the post would be housed within Homeland Security or within the White House, which would not require Senate confirmation. Appointing a person who is based within Homeland Security could be trickier because the department’s agency heads are all Senate-confirmed positions and, in the case of Immigration and Customs Enforcement and U.S. Customs and Border Protection, are longtime immigration officials with decades of experience dealing with the border.