"I think your government is committed to doing the right thing," Clinton said in a speech to a group of business leaders.

With 5.13 million cases, India has the second largest number of people infected with HIV after South Africa.

International health experts have warned that India's official figure is too low, and that the country may have surpassed South Africa. Others warn that India faces a major catastrophe unless it launches a massive effort to fight AIDS. Medical workers fear ignorance and the stigma attached to the disease could push India into the top slot over the next few years.

Clinton, who has made the battle against AIDS a focus of his post-presidential life, praised India's anti-AIDS campaigns but warning that the country can't afford to slack off in its efforts.

"You will move from being the world's number one worry to being the number one model if you follow through the plans you have," Clinton said.

Government officials quickly took credit for the drop in the infection rate -- the first such fall in years.

"This endorses that our policies are on the right track," S.Y. Quraishi, director-general for the National AIDS Control Organization, told reporters earlier.

Nevertheless, Quraishi said the government would continue to scale up its campaign against AIDS and would watch the figures for the next three years before concluding whether the trend has been reversed.

"We view these figures with a bit of caution," he said of the estimates, which were compiled by two independent research organizations.

In the past two years, the focus of the government's strategy has been on areas where the disease has a high prevalence and the most vulnerable groups such as sex workers, truckers and drug addicts. "This has really paid off," Quraishi said.

The spread of HIV/AIDS in India has been attributed to widespread migration of labor, low literacy levels -- leading to a low awareness about the disease and the manner in which it spreads -- gender disparities, and the prevalence of sexually transmitted diseases.

Another concern is the growing number of young girls and women who are infected with the disease and whose chances of getting proper care are reduced because women are undervalued in Indian society.

Clinton also praised the Indian pharmaceutical industry, which has been a leader in manufacturing low-cost generic drugs that help the poor and people in the developing world have access to the drugs that fight AIDS and HIV.

"The key to all of this has been the availability of low-cost medicines, and a lot of the credit goes to Indian companies," he said.