Washington (CNN) Mark Esper has formally stepped down from his role as acting defense secretary Monday after the Senate received his nomination from the White House to be confirmed for the permanent position.
Navy Secretary Richard Spencer has assumed the acting role, making him President Donald Trump's third acting defense secretary this year, and will serve in that job until Esper is confirmed by the Senate.
Esper's nomination hearing before the Senate Armed Services Committee is scheduled for Tuesday morning, as CNN has previously reported.
The Senate Armed Services Committee announced last week that it would expedite the process to hold a confirmation hearing despite only receiving Esper's formal nomination from the White House on Monday.
"At 3:04 pm today, the Senate received the President's formal nomination of Dr. Mark T. Esper to be Secretary of Defense. At that time, Dr. Esper ceased to serve as Acting Secretary of Defense and is solely serving as Secretary of the Army. As a result, as prescribed in Executive Order 13533, 'Providing an Order of Succession Within the Department of Defense,' ... Secretary of the Navy Richard Spencer became Acting Secretary of Defense," chief Pentagon spokesman Jonathan Hoffman said in a statement.
"As such, Secretary Spencer has the full authority and responsibility of the Secretary of Defense. The senior team supporting the Office of the Secretary remains in place to ensure institutional continuity," he said.
The announcement comes at a time when large number of senior roles at the Pentagon lack permanent appointees. Increased global tensions have prompted senators on both sides of the aisle to begin the confirmation process for Esper as they are eager for stable leadership after more than six months without a permanent defense secretary.
CNN has previously reported that Esper would have to step down from his acting role due to regulations until he is confirmed by the Senate and that Spencer would assume the position in the interim.
Esper will "cease to serve as the acting Secretary of Defense and will become solely serving as the Secretary of the Army," the Defense Department's chief of staff, Eric Chewning, told reporters at the Pentagon last week.
Trump announced his intention to nominate Esper, who had been serving as Army secretary, after Patrick Shanahan's nomination dramatically imploded last month.
Esper can continue to "receive" information while he goes through the confirmation process and will stay up to date on policy and some operational matters, according to Chewning. However, Esper will not receive the same level of intelligence briefings as the secretary of defense because many of the intelligence programs are on a need to know basis, he said.
Spencer will have full authority to make any operational or program decisions and not consult with Esper, Chewning added. Allies, including NATO members, will be notified of the transition by US ambassadors, he said.
Earlier this month, the Department of Defense confirmed to CNN that 18 senior roles were unfilled, providing a complete list of positions currently being filled by temporary officials.
The number grew to 19 when the Trump administration's pick to be chief of naval operations, Adm. William Moran, announced his decision to retire after his judgment was questioned over a professional relationship he maintained with a former Navy public affairs official who left the service amid allegations of sexual harassment and sexual assault.