The standoff has left an unprecedented three branches of the US military -- the Army, Navy and Marine Corps -- with leaders serving on an acting basis, while a number of other important positions are also unfilled.

"We're not going to change our policy on ensuring that every single service member has equitable access to reproductive health care," Deputy Pentagon Press Secretary Sabrina Singh told journalists.

"If you are a service member stationed in a state that has rolled back or restricted health care access, you are often stationed there because you were assigned there -- it is not that you chose to go there," she said.

"A service member in Alabama deserves to have the same access to health care as a service member in California, as a service member stationed in Korea."

The US Supreme Court in June 2022 struck down the nationwide right to abortion, meaning troops stationed in states that restricted or banned the procedure must now take leave and travel to areas where it is legal to obtain one.

The Defense Department responded by permitting service members to take administrative absences to receive "non-covered reproductive health care," and establishing travel allowances to help them cover costs.

Senator Tommy Tuberville, a Republican from Alabama, insists those efforts are illegal and has vowed to delay the approval of senior officers as well Defense Department civilian officials until they are reversed.

He is preventing more than 300 nominees from being quickly approved by the Senate via unanimous consent, and while lawmakers can still vote on nominations individually, that much more time-consuming process has not been used so far.