Some Republicans in Congress have tried to slow the change by requiring that all four military service chiefs -- who have previously opposed repeal of the policy -- be included in its certification. Rep. Duncan Hunter, R-Calif., plans to introduce a legislative amendment today.
"The four military service chiefs are far more closely connected to the day-to-day realities facing each respective service branch than those who are currently required to sign off on the repeal, including the president," Hunter said.
"Any movement toward implementation must be efficient and show respect for the culture and tradition unique to each service branch and the military as a whole," he said.
Democrats and some moderate Republicans have vowed to oppose any such change.