But White House press secretary Robert Gibbs conceded President Barack Obama has the final say on what to do about the ruling on the military policy involving gays and lesbians.
"I haven't really ... had a chance to talk to the president about this (expected appeal), this morning," Gibbs said. "I refer you to the Department of Justice on appeals and that sort of thing."
Under the "don't ask, don't tell" policy, the U.S. military tolerates serving homosexuals only if they don't openly declare their sexual orientation. A federal judge in Los Angeles issued an order Tuesday telling the military not to enforce the policy, declaring it unconstitutional.
Gibbs told reporters the best way to end the policy was for the U.S. Senate to follow the lead of the House and end the policy by law.
Meanwhile, U.S. Defense Secretary Robert Gates didn't comment on an expected appeal, but said ending the policy was a matter for Congress.
En route from Vietnam to Brussels, Gates told reporters traveling with him that much remains to be worked out before the Defense Department could implement a change allowing gays and lesbians to serve openly in the military, a Defense Department article said.
He said a Pentagon review panel is still researching the issue, and input from service members and their families remains to be compiled and evaluated, Gates noted.
"I feel very strongly that this is an action that needs to be taken by the Congress," Gates said, "and that it is an action that requires careful preparation and a lot of training. We have a lot of revision of regulations that has to be done."