NBC News spoke with two senior Republican congressional staffers, two senior Democratic congressional staffers and two other people briefed on the cost.

A little over two months after President Donald Trump announced a rebrand of the Department of Defense to rename it the Department of War, an NBC News report citing six people with knowledge of the matter has revealed the potential cost: up to $2 billion.

Defense Secretary Pete Hegseth teased the change on social media in September, writing, "DEPARTMENT OF WAR" and linking to a related Fox News report. The White House then confirmed as much to HuffPost, with an executive order about the plan following after.

The rename would require thousands of signs, placards, letterheads and badges to be changed, according to two senior Republican congressional staffers, two senior Democratic congressional staffers and two anonymous people briefed on the cost, per NBC News.

The four staffers and one of the people briefed added that new letterheads and signage alone could cost taxpayers $1 billion. The staffers said rewriting the code for all of the department`s websites and internal applications would also be significantly expensive.

Pentagon spokesperson Sean Parnell told the outlet in an emailed statement that a total cost for the change has yet to be determined, but that the new name will be "permanent," before blaming Democrats for the government shutdown and his lack of an exact figure.

A Department of War existed previously, specifically from 1789 to 1947. Trump claimed in June it was renamed with "Defense" because "we became politically correct."

The National Archives states it was renamed when a 1947 law combined the departments of the U.S. Army with those of the Navy and Air Force, and that this was called the National Military Establishment before being renamed in 1949 to the Department of Defense.

"Under the Trump administration, we are restoring the pride and the winning spirit of the United States military," Trump said Tuesday during a Veterans Day speech. "That`s why we have officially renamed the Department of Defense back to the original Department of War."

Earlier this year, the U.S. embarked on a series of lethal strikes against suspected drug smugglers in Caribbean and Pacific waters. Lawmakers from both sides of the aisle have decried the killings as "illegal" and "summary execution."

The determined effort to rename the Defense Department also notably arrives amid Trump`s purported efforts to reduce spending - by cutting millions of Americans off Medicaid and gutting federal agencies - which 10 Senate Democrats haven`t forgotten.

In a September letter to Congressional Budget Office director Phillip Swagel, they noted that the name change requires congressional approval, requested clear projected costs, and said it "appears to prioritize political theater over responsible governance."

The letter further stated, "Given the Trump administration`s repeated emphasis on fiscal restraint-particularly its aggressive use of illegal impoundments and now, unconstitutional pocket rescissions-this symbolic renaming is both wasteful and hypocritical."