India has fewer than 2.5 million people living with HIV/AIDS, a senior health official said on Wednesday, nearly 60 percent lower than the 5.7 million estimated by the United Nations.

"The new number is just under 2.5 million," the official, who is closely involved in India's AIDS control programme, told Reuters on condition of anonymity, ahead of the official release of the numbers due on Friday.

Top officials and health experts met in New Delhi on Friday to finalise the new figure, which came after a new population-based survey indicated last month that India's HIV estimate of 5.7 million - seen as the world's biggest caseload - was a huge overestimate.