A UN AIDS summit starting Wednesday must set key figures on how many people will get special treatment to hold back the disease which has killed nearly 30 million people in the past three decades.
And as 30 heads of state and government gather at the UN headquarters key funding nations are digging their heels in on how many should qualify for drugs and therapies which new research has showed is braking the spread of of AIDS.
Presidents Goodluck Jonathan of Nigeria, Paul Kagame of Rwanda and Ali Bongo of Gabon, whose country heads the Security Council in June, will be among leaders at the three day summit.
The Medecins Sans Frontieres (Doctors Without Borders) group has called on the summit to put nine million people on AIDS treatment over the next four years in the face of "strong opposition from several key funders."
There are an estimated 34 million people living with AIDS and more than nine million are still not getting treatment, according to UN statistics. About 6.6 million people are getting drugs and the rest do not know they have AIDS.
Negotiations over the figure, which could change the cost by hundreds of millions of dollars, continued right up to the start of the summit, diplomats said.
"The world needs an ambitious HIV/AIDS treatment target with a plan attached to make it a reality -- because it will be meaningless if countries aren't willing to come up with the cash and actions needed to break the back of the epidemic," said MSF's AIDS policy advisor Sharonann Lynch.
Funding for the global AIDS battle rose to 15.9 billion dollars a year by 2009 but has since declined after the international financial crisis.
UNAIDS, the UN agency coordinating action to halt the spread of the disease, says however that an additional six billion dollars a year could avert seven million deaths by 2020.
The money could be used for drugs which would bring down the annual number of new infections from 2.5 million in 2009 to one million by 2015.
UNAIDS executive director Michel Sidibe says that the anti-AIDS drugs have become a "gamechanger" in the health war.
But health groups say governments must take new action to keep the cost of medicines down. MSF says new drug combinations against AIDS can cost up to 50 times more than the first generation of pharmaceutical cocktails used to combat the disease.
And now that so many sufferers have seen their lives extended, the cost is skyrocketing.
"Ten years ago, our patients came to clinics in wheelbarrows often moments away from death because treatment was priced out of reach," said Tito von Schoen-Angerer, who worked in MSF's first AIDS treatment centre in Thailand.
"Thanks to affordable generic drugs we've watched treatment transform lives," he added.
Most of the leaders at the summit will be coming from Africa and other poor countries which are still bearing the brunt of the AIDS epidemic.
Thirty years after US epidemiologists first described the cases of five young homosexuals whose immune systems had been destroyed, 7,000 people a day are still being infected with the Acquired Immune Deficiency Syndrome.