The U.S. House’s four openly gay members have asked President Obama to issue a veto threat against a defense spending bill that includes a measure to delay repeal of “Don’t Ask, Don’t Tell.”

They sent the letter a week after the White House issued a statement threatening to veto the FY 2012 National Defense Authorization Act (NDAA) over several provisions. Although the White House statement “strongly objected” to three amendments that sought to delay repeal of “Don’t Ask, Don’t Tell” (DADT), it did not threaten veto over those provisions.

The Republican-dominated House approved the bill May 26 with a number of the provisions to which the White House objected, including the three DADT amendments.

The Democratic-dominated Senate is not expected to approve the DADT amendments in its version of the bill. But a House-Senate conference committee will eventually need to agree on a final version of the bill.

In their June 3 letter to the president, Reps. Barney Frank, Tammy Baldwin, Jared Polis, and David Cicilline said “it would be the best course for you to reaffirm your strong support” for repeal of the military’s ban on openly gay servicemembers “by making it explicit that you would veto a bill …which undermined the decision” to repeal “Don’t Ask Don’t Tell.”

Frank released the June 3 letter on Monday in a press release, saying that the DADT amendments, if left intact, “would make repeal very difficult in practice.”

Meanwhile, the Marine Corps has apparently missed its self-set target date for completing training in preparation for repeal of DADT. In an internal memo to the “Marine Corps total force” on February 16, Marine administrators said training of the final tier of personnel “should be complete by May 31.” The Marines have issued no statement indicating they have completed training and a press spokeswoman did not respond to a reporter’s inquiry.

Other service branches set later dates for completion of training. Pentagon officials said in April that the required “certification” of readiness to repeal DADT would likely be sent to Congress by mid-summer.

At a routine press conference at the White House Monday, Washington Blade reporter Chris Johnson asked Press Secretary Jay Carney whether President Obama hope for certification before Defense Secretary Robert Gates retires June 30. Gates, the Chairman of the Joint Chiefs of Staff, and the President are required, under the law to repeal DADT, to certify that the military is ready to repeal the law.

“I think the process is moving at the pace that we anticipated, and I also think that it’s the President’s policy and that it will be implemented regardless of who is Secretary of Defense,” said Carney.

“But the President—the administration is surely concerned that if we wait until Leon Panetta comes in there could be additional delays,” said Johnson.

“We don’t share that concern, no,” said Carney.

Admiral Mike Mullen, Chairman of the Joint Chiefs of Staff, is set to retire October 1. President Obama on May 30 announced that he has chosen U.S. Army General Martin Dempsey to replace Mullen.