"I am here to make it absolutely clear: The United States is committed and will remain committed to achieving an AIDS-free generation," Clinton told the international AIDS conference in Washington.

"We will not back off, we will not back down, we will fight for the resources to achieve this historic milestone."

Clinton's keynote speech sought to underscore Washington's dedication to the global AIDS fight amid fears that U.S. leadership might suffer as spending cuts and budget woes threaten a range of government programs.

Clinton announced more than $150 million in new U.S. spending initiatives geared toward leveraging progress against AIDS already achieved through new drug treatments, programs to stop mother-to-child transmission of HIV and the preventive effect of expanded voluntary male circumcision.

"This is a fight we can win. We've already come so far, too far to stop now," Clinton said. "HIV may be with us into the future until we finally achieve a cure, a vaccine. But the disease that HIV causes need not be with us."

The United Nations estimates that about 34 million people are living with the human immunodeficiency virus (HIV) that causes AIDS. But U.N. figures show that the number of worldwide AIDS-related deaths fell to 1.7 million last year from some 1.8 million in 2010, after peaking at 2.3 million in 2005.

An estimated 8 million people in lower-income countries are receiving antiretroviral drugs, and the United Nations has set a target to raise that to 15 million by 2015.

Funding for HIV prevention and treatment totaled $16.8 billion last year. Of that amount, $8.2 billion came from international sources including the United States, which donated 48 percent of it.

AIDS-FREE GENERATION IN SIGHT?

Clinton said the goal of an "AIDS free generation," which means that no child will be born with the virus, those already in their teens will be at less risk and those already infected will have access to treatment, was in sight.

U.S. funding for anti-retroviral drugs, the only treatments known to slow the disease, now covers close to 4.5 million people and should cover 6 million by the end of 2013, Clinton said.

The United States is also stepping up funding for voluntary male circumcision, which has been shown to cut the risk of female-to-male transmission by more than 60 percent in studies in Africa, the continent hardest hit by the disease.

Clinton said U.S. funds had supported 400,000 circumcision procedures since last December and announced that the United States would provide a further $40 million for South Africa's plans to provide voluntary circumcision to almost half a million men and boys in the coming year.

The United States will also step up funding for programs to help prevent mothers from passing along the HIV virus to their unborn children, providing $80 million to help improve treatment for HIV-positive pregnant women, Clinton said.

AT LONG LAST - WELCOME TO THE U.S.

This week's gathering in Washington is the first international AIDS conference in the United States since 1990, and follows a 2009 decision by the Obama administration to drop a standing U.S. ban on HIV-positive people entering the country.

Clinton, who was met by scattered chants and cheers as she started her speech, acknowledged the change.

"What would an AIDS conference be without a little protesting? We understand that," Clinton said. "Let me say five words we have not been able to say for too long: Welcome to the United States!"

And she called on governments to take steps to reach groups most at risk for HIV such as sex workers and men who have sex with men, urging an end to discrimination which has marginalized many of the most vulnerable people, particularly in Africa.

Clinton announced a total of almost $40 million in new U.S. funding for programs to reach these groups and said the world could not be complacent if the HIV virus is allowed to spread at society's margins.

"If we're going to beat AIDS we can't afford to avoid sensitive conversations and we can't fail to reach the people who are at the highest risk," Clinton said. "Humans might discriminate, but viruses do not."

(Editing by Warren Strobel and Cynthia Osterman)

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