WASHINGTON (AP) — The Army is planning a sweeping transformation that will merge or close headquarters, dump outdated vehicles and aircraft, slash as many as 1,000 headquarters staff in the Pentagon and shift personnel to units in the field, according to a new memo and U.S. officials familiar with the changes.

In a memo released Thursday, Defense Secretary Pete Hegseth ordered the transformation to “build a leaner, more lethal force.” Discussions about the changes have been going on for weeks, including decisions to combine a number of Army commands.

Col. Dave Butler, an Army spokesman, said the potential savings over five years would be nearly $40 billion.

U.S. officials said as many as 40 general officer slots could be cut as a result of the restructuring. They spoke on condition of anonymity to discuss personnel issues.

The changes come as the Pentagon is under pressure to slash spending and personnel as part of the broader federal government cuts 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 Training and Doctrine Command into one entity and merge 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 shifted 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 also have stymied later moves to chop programs.

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

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