Susan Walsh, Associated Press
This Nov. 24, 2014, file photo shows President Barack Obama, left, looking to Defense Secretary Chuck Hagel, right, as he talks about his resignation during an event in the State Dining Room of the White House in Washington. The Air Force's top official says Chuck Hagel's surprise resignation as Pentagon chief won't steal momentum from his plan -- announced only 18 days ago -- to make top-to-bottom changes in how the nuclear Air Force is managed.

WASHINGTON — The Air Force's top official says Chuck Hagel's surprise resignation as Pentagon chief won't steal momentum from his plan -- announced only 18 days ago -- to make top-to-bottom changes in how the nuclear Air Force is managed.

In an Associated Press interview Tuesday, Air Force Secretary Deborah Lee James called herself "not concerned" about losing political push for the ambitious Hagel agenda.

James said she has briefed President Barack Obama on the Air Force portion of the changes announced Nov. 14 by Hagel, who had ordered two in-depth reviews of the problems.

James said the administration remains committed to making big changes to ensure the future security and reliability of the nuclear force, which has suffered discipline and morale problems as well as leadership lapses.