Pentagon leaders will roll out a plan Friday that is expected to give the military services about three months to train their forces on the new law allowing gays to serve openly, officials said Wednesday.

The plan, they said, will outline the personnel, recruiting and other regulations that must be changed. It will describe three levels of training for the troops, their commanders and the key administrators, recruiters and other leaders who will have to help implement the changes.

Under that training schedule, full implementation of the law could begin later this summer. Once the training is complete, the president and his top military advisers must certify that lifting the ban won't hurt troops' ability to fight. Sixty days after certification, the law would take effect.

Word of the plan comes a day after President Barack Obama told the nation in his State of the Union address that the change was in sight.

Pentagon press secretary Geoff Morrell said senior defense and military leaders will provide an update Friday on how the Pentagon is proceeding on the implementation of the new law, which ended the Pentagon's 17-year-old "don't ask, don't tell" policy and will allow gays to serve openly for the first time in history.

Morrell declined to say more, but officials familiar with the plan described it on condition of anonymity because it has not been finalized or made public.

Details have been scarce as the military has scrambled to pull together the dozens of legal and policy changes that must be made by all the services in order to put the new law into effect.

The changes affect how troops are recruited, trained and discharged, as well as how same sex partners will be treated in terms of various health and other benefits.

Some will be easy to implement. For example, recruits will no longer be turned down because they are gay.

But others involving benefits, housing and the execution of the training program will be more complex.

According to officials, the training will be broken into three categories. One will be for administrators and other leaders who will have to be able to answer detailed questions about the new policy. The second will be for senior commanders who will have to enforce the policies and also be on the lookout for signs of unease or problems among service members.

The third group will be the general training for the troops. That is the one that is expected to be the most difficult to complete because service members are scattered around the world, and many are in various phases of deployment to war or heading home.

In his State of the Union speech Tuesday night, Obama declared that, "Starting this year, no American will be forbidden from serving the country they love because of who they love." He added, "It is time to leave behind the divisive battles of the past. It is time to move forward as one nation."

Although Obama did not describe any specific time frame, Pentagon leaders have repeatedly said they will move quickly but carefully to implement the law.

Advocates for gays have called for quick action.

"For years, experts have said that a swift repeal process, accompanied by strong leadership, is the best way to repeal 'don't ask, don't tell.'," Aaron Belkin of the Palm Center, a California think tank, said Wednesday. "In promising ... to implement the repeal of the ban this year, President Obama has demonstrated leadership and committed to the path that has been proven to be best not only for gay service members, but for all of those who currently serve."

The Servicemembers Legal Defense Network, however, wants officials to hurry along certification that the change won't hurt military effectiveness.

"We think there should be certification from the president, (Defense) Secretary Robert Gates and (Joint Chiefs of Staff) Chairman Michael Mullen in this quarter," the group said in a statement Wednesday. "We need to make 'Don't Ask' repeal a reality sooner rather than later."

— AP National Security Writer Robert Burns contributed to this report.