Speaking at the White House to mark World AIDS Day, the president said the United States would contribute $1 for every $2 pledged by other donors over the next three years to support The Global Fund, an international financing institution that fights AIDS, tuberculosis and malaria.
Obama also said he would redirect $100 million into a National Institutes of Health program to research a cure for HIV, the human immunodeficiency virus that causes AIDS.
"The United States should be at the forefront of new discoveries into how to put HIV into long-term remission without requiring lifelong therapies - or, better yet, eliminate it completely," Obama said at an event attended by Secretary of State John Kerry and software magnate Bill Gates, whose foundation has pledged up to $500 million for The Global Fund.
Obama also signed into law legislation authorizing an extension of a successful and popular program to combat AIDS worldwide, the President's Emergency Plan for AIDS Relief, known as PEPFAR.
PEPFAR funding has fallen 12 percent since 2010. Critics have accused Obama, a Democrat, of failing to show the same level of commitment to fighting AIDS as his Republican predecessor, Bush, who poured $15 billion into the program to combat AIDS worldwide.
Obama has argued that his administration has expanded the program's scope without increasing spending.