Kirstjen Nielsen, John Kelly's principal deputy chief of staff, has been nominated to serve as secretary of the Department of Homeland Security.
Nielsen is now the White House principal deputy chief of staff.
She previously served as special assistant to the president for prevention, preparedness and response on the White House Homeland Security Council under President George W. Bush and launched the Offices of Legislative Policy and Government Affairs at the Transportation Security Administration. They spoke on condition of anonymity to discuss deliberations before a formal announcement.
But Thompson said he had questions about her background, including her past work for the Bush administration. She was Kelly's top aide when the former four-star Marine general led the Department of Homeland Security (DHS) during the early months of the Trump administration.
Rep. Bennie G. Thompson, D-Miss., the ranking member of the Committee on Homeland Security, said in a statement he was pleased the president had made a decision on filling the post "after letting the critical national security position remain vacant as the nation faced multiple major hurricanes and a domestic terrorism attack".
Nielsen, a cybersecurity expert who served as Kelly's chief of staff when he was DHS secretary, accompanied him to the White House as his deputy and quickly emerged as a controversial presence. The White House had no immediate comment.
Mr. Kelly, who has relied on Ms. Nielsen's counsel and expertise since he was preparing for his January confirmation hearing to be Homeland Security secretary, had pushed hard for her selection.
"She would be the first person to run the department who has actually worked there", one person close to the Trump administration told Politico.