(The Hill) — The secretaries of the Navy, Air Force and Army are calling on Sen. Tommy Tuberville (R-Ala.) to release his hold on military promotions, accusing him of putting national security “at risk.”

“Any claim that holding up the promotions of top officers does not directly damage the military is wrong — plain and simple,” the three secretaries wrote in an op-ed published in The Washington Post on Monday. 

Navy Secretary Carlos Del Toro, Air Force Secretary Frank Kendall and Army Secretary Christine Wormuth said the military leaders are the “foundation of America’s enduring advantage” that is being “actively eroded” by Tuberville’s hold on promotions — which has lasted for more than six months.

At the center of the issue is a new Defense Department policy that provides paid leave and travel reimbursement for abortions. Tuberville claimed that it violates the Hyde Amendment, which prohibits federal funds from being used for abortions.

The secretaries argue the policy is “critical and necessary to meet our obligations to the force,” noting that it falls within the law and has been confirmed by the Justice Department’s Office of Legal Counsel. They also emphasized that the hold harms U.S. national security because it has prevented the Pentagon from placing 300 of its leaders in “critical posts” around the globe.

They also wrote in the op-ed that because of the block, military families are enduring costs and “genuine financial stress,” adding that some officers have had to relocate their families or maintain two residences. 

“These military leaders are being forced to endure costly separations from their families — a painful experience they have come to know from nearly 20 years of deployments to places such as Iraq and Afghanistan,” the secretaries wrote. “All because of the actions of a single senator.”

The top defense leaders also said they were concerned that some military officers may leave the service for other opportunities as a result of the hold, noting that the effect has also been “upending the lives of” more junior officers. They said service members from all different ranks could be believing that their service “is no longer valued by members of Congress, or by extension, the American public.”

“Throughout our careers in national security, we have deeply valued the bipartisan support shown for our service members and their families,” the secretaries continued. “But rather than seeking a resolution to this impasse in that spirit, Tuberville has suggested he is going to further escalate this confrontation by launching baseless political attacks against these men and women.”

Tuberville’s six-month hold on the positions has drawn criticism from figures on both sides of the aisle. According to a recent poll, a majority of likely Alabama voters want their senator to drop his hold on military promotions.