The executive order from U.S. President Donald Trump to rename the Department of Defense to the "Department of War" may incur costs up to $2 billion.

This information comes from NBC News citing several informed sources.

The article states that renaming the Pentagon will require replacing thousands of signs, posters, forms, and badges, as well as other items at U.S. military facilities worldwide.

According to four congressional officials and another source for NBC News, the new forms and signs for the "Department of War" could cost around $1 billion alone.

The cost will largely depend on the reconfiguration of codes for all internal and external Pentagon websites, as well as updates to software on both classified and unclassified systems, the NBC News sources added.

Pentagon spokesperson Sean Parnell responded that a final cost assessment for the name change is not available due to the "democrat-led government shutdown".

"This change, which pays tribute to our proud heritage, is necessary as it reflects the core mission of the Department: to win wars," he added.

In September, President Donald Trump signed an executive order granting the U.S. Department of Defense an additional title – "Department of War".

From now on, the U.S. Secretary of Defense is authorized to use the additional title – Secretary of War – in official correspondence, public communications, ceremonial events, and non-statutory executive documents.