General Martin Dempsey, former Chairman of the Joint Chiefs of Staff, has slammed President Trump’s call for the Department of Defense to create a new branch of the military, called the “Space Force.”

On Friday, the Irish American retired U.S. army general said Trump “raffled off” the Space Force and urged Congress, who would have to approve the establishment of a new military branch, to step in, Business Insider reports.

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"71 years ago today, the Department of Defense was established after extensive study with a clear mission codified in legislation," Dempsey tweeted. "Yesterday, the Space Force was raffled off. However, the Congress is responsible for 'raising and sustaining' the military. They must sort this out."

71 years ago today, the Department of Defense was established after extensive study with a clear mission codified in legislation. Yesterday, the Space Force was raffled off. However, the Congress is responsible for “raising and sustaining” the military. They must sort this out.

— GEN(R) Marty Dempsey (@Martin_Dempsey) August 10, 2018

The president called for a Space Force in June and is moving forward with the plan, despite opposition from military officials.

On Thursday at the Pentagon, Vice President Mike Pence revealed the administration's plan to move forward with the Space Force, which would be the sixth branch of the military and the first new military branch since the Air Force in 1947.

“The time has come to establish the United States Space Force," Pence said.

"Our administration will soon take action to implement these recommendations with the objective of establishing the United States Department of the Space Force by the year 2020," Pence added.

Space Force all the way!

— Donald J. Trump (@realDonaldTrump) August 9, 2018

Other senior military officials have criticized the push for a Space Force over concerns about the cost and the effect on current military branches.

The White House intends to introduce legislation by early next year.

General Martin Dempsey.Wikipedia/Public Domain