President Trump on Monday announced the creation of a new, sixth branch of the military, the Space Force, to be an independent force on par with existing branches. The move came despite reservations from some top military leaders.

WASHINGTON — President Donald Trump on Monday appeared to sign an executive order directing the Pentagon to create a new ”Space Force,” a move that could radically transform the U.S. military by pulling space functions variously owned by the Air Force, Navy and other military branches into a single independent service.

But while the president’s support for a new military branch is notable, experts -- and a powerful member of Congress -- believe Trump still needs the support of Congress to make a space force happen.

“I am hereby directing the Department of Defense and Pentagon to immediately begin the process necessary to establish a Space Force as the sixth branch of the armed forces,” Trump said during a meeting of the National Space Council.

“That’s a big statement. We are going to have the Air Force and we are going to have the Space Force. Separate but equal. It is going to be something. So important,” Trump added. “General Dunford, if you would carry that assignment out, I would be very greatly honored.”

Dunford responded in the affirmative, telling Trump, “We got you.”

According to a White House pool report, the president signed the executive order establishing the Space Force at about 12:36 p.m. EST.

However, a readout issued from the White House later that day of the executive order contained no language related to the creation of a new military branch, leaving open the question of whether Trump has actually issued formal guidance to the military.

The Air Force referred all questions to the Office of the Secretary of Defense, which did not respond immediately to requests for comment.

However, a defense official, speaking on background, said “The Joint Staff will work closely with the Office of the Secretary of Defense, other DoD stakeholders and the Congress to implement the President's guidance."

Trump’s support for creating a separate branch for space is a break from his own adminsitration’s stance last year, as well as that of Secretary of Defense Jim Mattis.

“At a time when we are trying to integrate the Department’s joint warfighting functions, I do not wish to add a separate service that would likely present a narrower and even parochial approach to space operations vice an integrated one we’re constructing under our current approach,” Mattis wrote in a 2017 letter to members of Congress.

But in recent months, Trump has signaled he was intrigued by the idea of a stand alone space force, saying in a May 1 speech that “We’re actually thinking of a sixth” military branch for space.

At the time, that statement confounded Air Force leaders who had publicly opposed the creation of a separate space service, leading them to adopt a softer tone when talking about the potential for Space Force to avoid being seen as out of step with Trump.

“Establishing a service branch requires congressional action.” House Armed Services Tactical Air and Land Forces Subcommittee chair Mike Turner, R-Ohio

This time, however, Trump’s announcement tracks with the Pentagon’s schedule for an interim report on whether to establish an independent space corps. Deputy Secretary of Defense Patrick Shanahan said in April that it was on track to be wrapped up on June 1. The final report, which would be sent to Congress, is due in August.

Trump’s announcement was characteristically vague, but experts say that any new branch would have to come through an act of Congress.

“The Congress alone has the power to establish a new branch of the military and to establish the positions of senior executive officials to lead such a department,” said Jonathan Turley, a professor at Georgetown University’s law school who has studied constitutional issues relating to the military. “While the Pentagon can informally create study or working groups, it has no such authority.”

The president can have the military lay the groundwork for a future new branch, Turley said, which is close to what Trump seemed to be getting at.

“What the President can do is to order the study and proposal for a new branch, which would ultimately go to Congress of any authorization and appropriations,” he said.

Todd Harrison, an expert with the Center for Strategic and International Studies, agreed, tweeting Monday that “The president can't just create a new military service on his own. It requires congressional authorization..”

“So the near-term practical effect of all this is that the president can direct DoD to come up with a plan and start preparing to create a Space Force, but he still needs congress to authorize it,” Harrison continued.

And while sources on Capitol Hill said they believe Trump does have the authority to establish the new military branch, and that their attention will now turn to funding and missions for the new Space Force, at least one Republican member of Congress made his stance clear.

“Establishing a service branch requires congressional action,” House Armed Services Tactical Air and Land Forces Subcommittee chair Mike Turner, R-Ohio. “We still don’t know what a Space Force would do, who is going to be in it, or how much is it going to cost.

“The congressionally mandated report evaluating a Space Force to answer those questions is due in August,” Turner added. “After we get the report that we required as a legislative body and the President signed off on, then this issue can be appropriately evaluated for what’s best for national security.”

Congress reacts

Trump’s announcement also left it unclear whether this new space force will rest under the Department of the Air Force — much like the Marine Corps is a component of the Department of the Navy — or whether a new “Department of the Space Force” will also be created.

Rep. Mike Rogers, R-Ala., the head of the House Armed Services strategic forces subcommittee, tweeted out his support for Trump’s order. Rogers had previously proposed a separate space service as part of Congress’ annual defense policy bill.

However, lawmakers and experts also immediately registered their opposition to the announcement.

Sen. Bill Nelson, (D-Fla.), the top Democrat on the Senate Commerce Committee that oversees nonmilitary space programs, tweeted that now was not the right time to establish a separate space force.

Harrison noted that the infrastructure may already exist to smooth the creation of a space force.

“Creating a Space Force would not necessarily mean a huge increase in funding. We already have space forces within the military, this would just be reorganizing them under a single chain of command,” he tweeted. “Yes, there would be some extra overhead costs, but it doesn't have to be huge.”

But David Deptula, a retired Air Force lieutenant general and currently dean of the Mitchell Institute for Aerospace Studies, questioned whether the administration had hammered down the details needed to successfully consolidate the military’s space functions into a single service.

“This is another case of ready, fire, aim,” he said.

David Larter, Joe Gould, Tara Copp and Leo Shane III contributed to this report. This story is developing.