WASHINGTON — Congress is expecting a report on how the Space Force will incorporate reserve forces on March 19, but the Space Force’s top civilian hinted Tuesday that the document may not go as far as establishing a Space National Guard just yet.

“We anticipate very much that there will be a Guard and reserve presence [in the Space Force], but that isn’t something we’re rushing to. We have, from Congress, an expectation of a design next year,” Air Force Secretary Barbara Barrett, who is also the civilian leader of the Space Force, said during a March 10 event.

The Defense Department is set to deliver a congressionally mandated “Space Force Total Management Plan” to Capitol Hill as early as next week, amid speculation about the role space-focused National Guard units could play in the new service.

The National Guard has about 1,500 space personnel: 1,100 in the Air National Guard and 400 in the Army National Guard. Those space forces and missions are concentrated in eight states — Colorado, California, Alaska, Hawaii, Florida, New York, Ohio and Arkansas — as well as the territory of Guam.

Although Barrett said those units would play a “significant role” in the Space Force, she stopped short of saying that she would advocate for a Space National Guard with the same structure as the Army or Air National Guards.

“We, again, are looking at building a system for the future and not just adopting what it’s been,” she said. “We wouldn’t anticipate 54 different state and territorial entities, but taking a clean sheet of paper and looking at how would we design a Guard and reserve element — or whatever it might be called — that would take that role and have the augmenting capability and local capability the Guard and reserve demonstrates.”

Defense Department officials leading the Space Force establishment have maintained that the process must happen methodically to ensure that bureaucracy is not created and that the new service is optimally organized.

However, the National Guard has strongly advocated for a separate Space National Guard, and several adjutant generals told reporters last month that they are prepared to work through Congress if the Pentagon fails to create one.

“We are strongly advocating for a Space National Guard, and that’s being received very well by the members on the Hill,” Maj. Gen. David Baldwin, the National Guard’s adjutant general from California, said in February. “Whether we allow [the Office of the Secretary of Defense] to go through their process to come to the conclusion on their own that we need a Space National Guard, or we leverage Congress and we have Congress put it in the [defense policy bill] and make it happen, remains to be seen.

The National Guard Bureau is not interested in creating a Space National Guard branch for every U.S. state and territory, but would instead require a small amount of additional overhead for the states that already have Guard units performing space missions, Maj. Gen. James Eifert, adjutant general for Florida, added at the same roundtable.

“We’re a proven model,” he said. “We’re not big fans of another yearlong study to examine the same things that we’ve already spent some time studying.”

At the event on Tuesday, Barrett did not elaborate on the options under consideration. Previously, Baldwin had said that the department was looking at dividing the Space Force into full- and part-time positions, eliminating the reserve component entirely, among other models.