WASHINGTON - A proposal to step up the repeal of the ban on gays and lesbians serving openly in the military, but still allow the Pentagon time - perhaps years - to implement the new policy, won the White House's backing Monday after administration officials met with gay-rights activists.

The White House budget office sent a letter supporting a congressional proposal to remove the Clinton-era "don't ask, don't tell" law even as the Pentagon studies how to introduce a new policy.

Implementation would still require the approval of President Obama, Defense Secretary Robert M. Gates, and the chairman of the Joint Chiefs of Staff, Adm. Mike Mullen, and the proposed amendment would have no effect on current practice.

"The proposed amendment will allow for completion of the comprehensive review, enable the Department of Defense to assess the results of the review, and ensure that the implementation of the repeal is consistent with standards of military readiness, effectiveness, unit cohesion, recruiting and retention," budget chief Peter Orszag said in identical letters to Pennsylvania Rep. Patrick Murphy, Connecticut Sen. Joe Lieberman, and Michigan Sen. Carl Levin - the Democrats leading the repeal push.

Murphy, an Iraq war veteran, was expected to introduce the legislative proposal Tuesday. Gay-rights groups urged a quick vote, which could come as early as Thursday.

"Without a repeal vote by Congress this year, the Pentagon's hands are tied and the armed forces will be forced to continue adhering to the discriminatory 'don't ask, don't tell' law," said Joe Solmonese, president of the Human Rights Campaign.

The White House had hoped lawmakers would delay action until Pentagon officials had completed their study so fellow Democrats would not face criticism that they moved too quickly or too far ahead of public opinion in this election year.

Instead, administration officials recognized it could not stop Congress in its effort to repeal the 1993 restriction, and joined the negotiations.

Hours after activists met at the White House, top Democratic lawmakers met on Capitol Hill and approved the final version of a brokered deal that adds the repeal to the annual defense spending bill.

Obama called for the repeal during his State of the Union address this year. Gates and Mullen have echoed his view but have cautioned that any action must be measured.

In a speech last year at the Army War College in Carlisle, Pa., Gates noted that the 1948 executive order for racial integration took five years to implement. "I'm not saying that's a model for this, but I'm saying that I believe this is something that needs to be done very, very carefully," he said then.

The administration has argued that any repeal should start in Congress and have the backing of top military leaders.

On Capitol Hill, the third-ranking House Republican promised unified GOP opposition to lifting the ban.

"The American people don't want the American military to be used to advance a liberal political agenda," said Mike Pence of Indiana. "And House Republicans will stand on that principle."

A Gallup poll earlier this month found that 70 percent of Americans favored allowing gays and lesbians to serve openly.