The White House has asked a US appeals court to suspend a judge's decision permitting gays to serve openly in the military, while it appeals against it.
The military began accepting gay recruits this week after a judge struck down the "don't ask, don't tell" policy barring openly gay people from serving.
The US defence department had warned gay recruits that an appeal could come.
Judge Virginia Phillips refused a request from the Pentagon this week to reinstate the ban.
The Obama administration says it wants the US Court of Appeals for the 9th Circuit in San Francisco to grant an emergency stay while the government prepares its appeal against the ruling by the California judge.
President Barack Obama has said he supports getting rid of the policy, but his administration believes that overturning it immediately could cause problems for the military.
The Justice Department said in its latest appeals court filing that leaving Judge Phillips's decision in place could create uncertainty for the "status of service members who may reveal their sexual orientation in reliance on the district court's decision and injunction".
The court papers added that developing "training and guidance" in relation to a change in the "don't ask, don't tell" policy would take time and effort.
'Violating free speech'Judge Phillips declared that the policy violated gay military members' rights to free speech and to equal protection under the law.
Some gay rights groups were planning to send individuals to military recruiting stations on Wednesday to enlist in hopes of testing the new decision.
Democrats in the US Senate attempted to overturn the policy in September, but failed to get the necessary votes. The House of Representatives approved measures to change the policy in May.
Meanwhile, US Secretary of State Hillary Clinton voiced her support for gay teenagers through a video message posted on Tuesday on the website YouTube, saying "hang in there and ask for help".
BBC News
