A senior defense official on Wednesday detailed the projects construction projects affected by Defense Secretary Mark Esper's approval to divert $3.6 billion in military construction funding to a wall at the southern border.

The movement of cash would affect 127 military projects across a total of 23 states, 21 countries and three U.S. territories -- Guam, Puerto Rico and the Virgin Islands.

Construction projects deferred at the 23 U.S. bases will include a "space control facility" at Peterson Air Force Base, home to the recently established U.S. Space Command.

Another project deferred: a missile interceptor field in Fort Greely, Alaska, with the intended purpose of shooting down ballistic missiles launched from North Korea or other rogue states. However, the project was not supposed to begin until 2021, and was for two "backup" silos for the 44 missile interceptors already on alert.

The senior defense official said the U.S. notified its allies Wednesday of the cuts. Congress was notified beginning Tuesday, the official said.

DEFENSE SECRETARY SIGNS OFF ON SPENDING $3.6B TO BUILD 175 MILES OF BORDER WALL

Overseas, maintenance and infrastructure projects across more than a dozen airbases were put on hold. Funds to build two Special Operations facilities in Estonia also were paused.

In addition, six U.S. military elementary schools and the U.S. Military Academy at West Point were affected by the cuts. Officials said West Point will have to wait on funds for a new parking structure.

Many Senate Democrats said they were unhappy with the president's decision to divert military funding for the border wall. "Congress appropriated these funds for specific military construction projects, and that's how the funds should be used," Sen. Dianne Feinstein, D-Calif., said in a statement. "When the Senate returns next week, we should immediately pass a resolution of disapproval to block this unconstitutional action," she added.

TRUMP TOUTS BORDER WALL PROGRESS AS PENTAGON SIGNS OFF ON FUNDING TRANSFER

Sen. Minority Leader Chuck Schumer, D-N.Y., called the move by the Trump administration a "slap in the face to the members of the Armed Forces."

And Rep. Debbie Wasserman Schultz, D-Fla., tweeted that "Trump is about to weaken our national security" to pay for "his xenophobic border wall."

President Trump earlier Wednesday said construction of the wall was moving along "rapidly." He said he expected "close to 500 miles of wall" to be "almost complete if not complete" just after the 2020 election.

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“We’re building different sections simultaneously,” Trump said, stating that by the end of 2020, crews will have built wall sections to “take care of all the areas we wanted,” as well as “some of the marginal areas” that were of a lower priority.

Various forms of barrier are already in place on 654 miles of the border, roughly a third of the total border. The administration already had awarded $2.8 billion in contracts for border wall strengthening, after an August Supreme Court ruling cleared the way for the funding.

Fox News' Ronn Blitzer and Jason Donner contributed to this report.