The U.S. Army is planning a major overhaul aimed at streamlining operations, which will involve merging or closing headquarters, retiring outdated vehicles and aircraft, reducing Pentagon staff by up to 1,000, and reallocating personnel to field units, according to a new memo and U.S. officials familiar with the changes.

In a memo released Thursday, Defense Secretary Pete Hegseth outlined the transformation plan, calling for a "leaner, more lethal force." Discussions about the restructuring have been ongoing for weeks, including plans to consolidate several Army commands.

Army spokesperson Col. Dave Butler said the changes could result in nearly $40 billion in savings over the next five years.

Officials also noted that as many as 40 general officer positions could be eliminated as part of the restructuring, speaking on condition of anonymity to discuss personnel matters.

The changes come as the Pentagon faces pressure to cut spending and personnel as part of broader federal government reductions pushed by President Donald Trump's administration and ally Elon Musk's Department of Government Efficiency.

In his memo, Hegseth said the Army must eliminate wasteful spending and prioritize improvements to air and missile defense, long-range fires, cyber, electronic warfare, and counter-space capabilities.

Specifically, he said the Army must merge Army Futures Command and the Training and Doctrine Command into one entity and combine Forces Command, Army North, and Army South into a single headquarters "focused on homeland defense and partnership with our Western Hemisphere allies."

In addition, he called for the Army to consolidate units, including Joint Munitions Command and Sustainment Command, as well as operations at various depots and arsenals.

Officials said that while the mergers will result in fewer staff positions, there won’t be a decrease in the Army’s overall size. Instead, soldiers would be reassigned to other posts.

On the chopping block would be legacy weapons and equipment programs, such as the Humvee and some helicopter formations, along with a number of armor and aviation units across the active-duty forces, National Guard, and Reserve. The units were not identified.

A key issue, however, will be Congress.

For years, lawmakers have rejected Army and Pentagon efforts to kill a wide range of programs, often because they are located in members' home districts.

Defense Department and service leaders learned long ago to spread headquarters, depots, troops, and installations across the country to maximize congressional support. But those efforts have also hindered later moves to eliminate programs.

It’s unclear whether the House and Senate will allow all of the cuts or simply add money back to the budget to preserve some programs.