(CNN)The US Air Force's decision-making process to move Space Command headquarters from Colorado Springs to Alabama had "significant shortfalls in its transparency and credibility," according to a report released Thursday by the Government Accountability Office (GAO).

       Space Command is the nation's newest warfighting combatant command, responsible for all military operations in outer space. The location of its headquarters has been the subject of intense debate since the final days of the Trump presidency when the administration recommended relocating it from Peterson Space Force Base in Colorado Springs to Redstone Arsenal in Huntsville, Alabama.

       "Each of the senior military officials we interviewed stressed the importance of U.S. Space Command reaching full operational capability as soon as possible in order to counter national security threats and noted that the potential need to relocate personnel constituted an associated risk," according to the report. But the unclassified version of the GAO report that was released publicly did not weigh in on if the proposed relocation should be reversed. Instead, the report simply recommends "that the Air Force develop guidance for future strategic basing decisions."

       The GAO review and a separate investigation by the Pentagon's Inspector General was requested in February 2021 by Colorado lawmakers who argued that the decision to relocate Space Command's headquarters was politically motivated and posed a risk to national security.

       "Over the past year, we've repeatedly raised concerns that the previous administration used a flawed, untested, and inconsistent process to select a location for US Space Command. The reports from the Government Accountability Office and the Department of Defense Inspector General both confirm that the basing process lacked integrity and neglected key national security considerations," Colorado's US Sens. Michael Bennet and John Hickenlooper and Reps. Doug Lamborn and Jason Crow said in a joint statement.

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       But the Pentagon's Inspector General found the basing decision "complied with federal law and DOD policy and that the process was reasonable," prompting Sen. Tommy Tuberville of Alabama to accuse Colorado lawmakers of suffering from "sore loser syndrome."

       "At this point, the biggest thing standing in the way of SPACECOM is political inertia and sore loser syndrome, each a detriment to US military effectiveness. It's time we embrace the Air Force's decision and move forward together," Tuberville said.

       Colorado lawmakers are still urging the Biden administration to reconsider. During a hearing last month, Air Force Secretary Frank Kendall said "we are all hoping to move forward with a final decision as quickly as we can."