After criticism that its new inclusiveness to gay and lesbian troops did not include equal openness toward transgender servicemen and women, the Pentagon said Monday it would begin to take steps to lift that ban too, starting with forming a study group on how to implement the change.

"At my direction, the working group will start with the presumption that transgender persons can serve openly without adverse impact on military effectiveness and readiness, unless and except where objective, practical impediments are identified," said Secretary of Defense Ash Carter.

The group will be tasked "to study over the next six months the policy and readiness implications of welcoming transgender persons to serve openly."

The move follows scrutiny by each of the services on their individual separation practices toward transgender troops. Previously, the process to discharge a service member who was found to be transgender could be initiated by a service member's direct commanding officer.

Until the policy is lifted, Carter directed that all cases where a transgender servicemember is being targeted for separation from the U.S. Armed Forces "be elevated" to Under Secretary of Defense for Personnel Brad Carson, who will review the cases.