However, despite having only taken the reins in late March, he has already provided enough fodder to create friction with the White House, according to NBC News. The administration insider admitted that Mullin messed up, signing off on the plan without a green light from the White House. White House border czar Tom Homan is particularly perturbed by his possible ascension, they added. “Secretary Mullin is working hard to implement the President’s immigration enforcement agenda,” White House spokeswoman Abigail Jackson said. White House spokesperson Abigail Jackson had a similar line, telling the Beast: “Secretary Mullin is working hard to implement the president’s immigration enforcement agenda.