President Barack Obama will sign a landmark gay rights bill on Wednesday morning.

The president will sign into law legislation that will allow gay and bisexual troops to serve openly in the military, ending the 1993 law known as “Don't Ask, Don't Tell” put in place by President Bill Clinton.

Before the law, gay men and lesbians were barred from service.

Clinton, who promised to change the policy, instead compromised. The policy he backed allows gay troops to serve so long as they remain closeted and celibate. More than 13,000 service members have been discharged for violating the policy.

As a candidate, Obama pledged to end the law. He reiterated his promise in this year's State of the Union speech.

“I will work with Congress and our military to finally repeal the law that denies gay Americans the right to serve the country they love because of who they are,” he said in January.

“It's the right thing to do,” he added to thunderous applause.

But gay rights activists questioned Obama's commitment to repeal due mostly to his administration's ongoing efforts to defend the law in the courts. In three separate cases the administration argued it had an obligation to defend the laws enacted by Congress.

Obama praised passage of repeal, which was achieved in the Senate after two unsuccessful attempts.

“Gay and lesbian service members – brave Americans who enable our freedoms – will no longer have to hide who they are,” Obama said in an email to supporters after the weekend vote. “The fight for civil rights, a struggle that continues, will no longer include this one.”

Implementation is expected to take months and supporters of repeal are cautioning gay troops not to come out yet.

“The bottom line: for now, gay, lesbian, and bisexual service members must remain cautiously closeted,” Aubrey Sarvis, executive director for Servicemembers Legal Defense Network (SLDN), the largest group lobbying for repeal, said in a statement.

The signing ceremony is expected to take place at 9:30AM in an auditorium at the Interior Department.