Obama announced the pledge to the Global Fund to Fight AIDS, tuberculosis and malaria at the White House during his remarks noting World AIDS Day.
"The United States will contribute $1 for every $2 pledged by other donors over the next three years, up to $5 billion total from the United States," Obama said in remarks recognizing World AIDS Day, which was Sunday. "And the United Kingdom has made a similar promise."
"So, today, I want to urge all of those who are attending the Global Fund's replenishment meetings [in Washington] both today and tomorrow, to take up this commitment," he said. "Don't leave our money on the table."
Obama also announced the National Institutes of Health will invest $100 million in re-prioritized funding in the next three years to launch a new initiative to find a cure for human immunodeficiency virus, which causes AIDS.
"We can't change the past or undo its wrenching pain. But what we can do and what we have to do is to chart a different future, guided by our love for those we could not save," Obama said.
He said his administration would work toward the day "when all men and women can protect themselves from infection, a day when all people with HIV have access to the treatments that extend their lives, the day when there are no babies being born with HIV or AIDS, and when we achieve at long last what was once hard to imagine, and that is an AIDS-free generation."
Obama later signed into law the "PEPFAR Stewardship and Oversight Act of 2013," to reauthorize the President's Emergency Plan for AIDS Relief he inherited from President George W. Bush.
During his World AIDS Day remarks, Obama called Bush's PEPFAR a "phenomenal" program that has helped millions of people around the globe receive lifesaving treatment.
Looking ahead, he said, it was time for the world to set new goals, including getting a permanent PEPFAR leader.
"And once we do, one of our first items of business will be to convening a meeting early next year so the United States and our partners worldwide ... can sit around one table and develop joint HIV prevention and treatment goals for the countries where we and the Global Fund do business," Obama said.