President Obama on Friday will nominate Jeh Johnson, a former senior Pentagon official, to replace Janet Napolitano as Homeland Security Secretary, according to a senior administration official.

“The president is selecting Johnson because he is one the most highly qualified and respected national security leaders, having served as the senior lawyer for the largest government agency in the world,” said a senior administration official. “During his tenure at the Department of Defense, he was known for his sound judgment and counsel.”

Obama will make the announcement at the White House at 2 p.m. Friday, the official said.

Johnson, as the Pentagon’s top lawyer, played a key role in developing the administration’s drone campaign overseas as well as the repeal of the ban on openly gay members in the armed forces.

“[Johnson] was responsible for the prior legal review and approval of every military operation approved by the President and Secretary of Defense,” the administration official added.

Napolitano recently stepped down from her position to lead the University of California system.

The DHS post requires Senate confirmation.

If confirmed, Johnson would face a number of challenges at Homeland Security, which has faced criticism from conservative lawmaker who say the department must do more to protect the U.S. border and over concerns about over-intrusive security procedures at airports.