Obama said DOMA should go the way of the U.S. military's now ended "don't ask, don't tell" policy for homosexuals.
"I vowed to keep up the fight against the so-called Defense of Marriage Act," he said at the 15th annual Human Rights Campaign national dinner in Washington. "There's a bill to repeal this discriminatory law in Congress, and I want to see that passed. But until we reach that day, my administration is no longer defending DOMA in the courts.
"I believe the law runs counter to the Constitution, and it's time for it to end once and for all. It should join 'don't ask, don't tell' in the history books."
Obama also took the opportunity to list other gay-friendly advances his administration has pushed forward during his 2 1/2 years in office, including passage of a hate crimes bill, an executive order for hospitals that accept Medicare or Medicaid to treat gay partners "just as they do straight partners," lifting the travel ban for those with HIV and implementation of a comprehensive national strategy to fight HIV/AIDS.
Still, he said, "we have more work to do" and he urged is audience to "feel encouraged."
"I don't have to tell you how many are still denied their basic rights -- Americans who are still made to feel like second-class citizens, who have to live a lie to keep their jobs, or who are afraid to walk the street, or down the hall at school," Obama said. "Many of you have devoted your lives to the cause of equality. So you know what we have to do; we've got more work ahead of us.
"I need your help to fight for equality, to pass a repeal of DOMA, to pass an inclusive employment non-discrimination bill so that being gay is never again a fire-able offense in America."