While praising the "tremendous progress" made in the battle against AIDS, President Barack Obama also expressed hope of continuing the determined fight against the disease that has claimed 25 million lives worldwide.
"At a time when so many men and women are living with HIV and AIDS every day, let's also recommit ourselves to build on the tremendous progress we've made both in preventing and treating the disease and ending the stigma and discrimination that too often surround it," Obama said in an online video.
The Empire State Building was among about 80 iconic landmarks in a dozen countries turning red at night to mark World AIDS Day.
The operation is led by (RED), a group founded by rock singer Bono, to drum up support for a campaign to end mother-to-child transmission of the deadly HIV virus by 2015.
As Obama commemorated the day of awareness, dozens of people protested outside the White House in a mock funeral procession to denounce the lack of access to care for the most destitute.
Philadelphia pastor Reverend Christopher Comer "implored the president to do more to keep his campaign pledges," as protesters around him sung gospels.
The Obama administration launched an ambitious plan in July to reduce by 25 percent each year the number of new infections in the United States by 2015.
"It's my hope that together we can move closer to the day when we eliminate this disease from the face of the Earth," Obama said.
His administration has set forth a comprehensive National HIV-AIDS Strategy that sets targets for the United States. Federal funds for the research reached 2.8 billion dollars in 2009.
In addition, the United States helped provide life-saving anti-retroviral treatment for 3.2 million men, women and children worldwide through the President's Emergency Plan for AIDS Relief (PEPFAR) this year, up by three-quarters of a million people in 2009, according to the State Department.
"We have saved millions of lives from AIDS over the past decade. By investing in what we know works, we can save millions more in the future," Secretary of State Hillary Clinton said in a statement.
The United States has committed to support over four million people on treatment -- double the number of patients during the first five years of PEPFAR, which then-president George W. Bush launched in 2004.
The United States this year also pledged four billion dollars between 2011 and 2013 to the Global Fund to Fight AIDS, Tuberculosis and Malaria, a partnership between governments, civil society, the private sector and communities affected by the three killer diseases.
The Global Fund has become the main source of finance for programs to fight AIDS, TB and malaria since it was set up in 2002. Its ultimate aim is to "free the world of the burden" of the three illnesses, of which AIDS is the biggest killer.
Former president Bill Clinton hailed "dramatic progress" in combating the disease, noting that when he left office in 2001 only 200,000 of the nearly 36 million people living with HIV/AIDS were receiving treatment.
"In spite of these efforts, only one-third of people who need treatment are receiving it," Clinton warned in an op-ed published in the British newspaper The Independent.
"We risk losing our momentum, unless we find new ways to fill the gaps left by reductions in government funding caused by the global economic crisis. And we need to save more lives with the money we do have."
AIDS-related deaths were estimated at about 1.8 million globally last year by the UN agency for the disease. Many of those who died from the disease also had tuberculosis, and 1.3 million victims were in Africa.
Malaria claimed around one million lives in 2008 and tuberculosis about 1.7 million last year, according to World Health Organization figures.