UN Secretary General Ban Ki-moon has sought a renewed commitment from governments to tackle the global HIV/AIDS epidemic which has already claimed more than 25 million lives worldwide and devastated communities, especially in Africa.

In a message on the occasion of 20th World Aids Day, Ban called for strong leadership to take on the deadly disease without which, he said, "we will not get ahead of the epidemic."

While "tangible and remarkable" progress has been made in a number of areas, including reducing infections and providing care, he emphasised the need to do more on various other fronts.

"It is our crucial mission to ensure that everyone can access HIV prevention, treatment, care and support," he said, recalling the pledge made by all Governments last year to work towards universal access by 2010.

The day is being held amidst questions being raised, whether the UN exaggerated the extent of epidemic to get funds. A recent UN report had revised the figures downwards, giving ground to critics to stress that other equally deadly diseased are being ignored.

The world body had denied that it had doctored the figures, with its officials maintaining that they now had better methodology to calculate the extent of the epidemic.

The Secretary General also emphasised the need for leadership among Governments in fully understanding the epidemic, so that resources go where they are most needed. In addition, he pledged to ensure that the UN becomes a model in responding to the virus. 

Executive Director of the Joint UN Programme on HIV/AIDS (UNAIDS) Dr Peter Piot said, the challenge now is to keep AIDS at the top of the agenda.

"The epidemic reached global proportions precisely because it took so long for the world to act," he said. "And although we are beginning to make progress, there remains a long way to go."

Citing a serious shortfall in resources for AIDS, and prevailing stigma and discrimination around the disease, he noted that two-thirds of those who require anti-retroviral treatment are unable to access it.

"Less than one in ten people at risk of HIV infection have the means to protect themselves," he said.

Piot stressed that sustaining leadership and accelerating action on AIDS isn't just an imperative for politicians.

 "It involves religious leaders, community, youth and council leaders, chief executives and trade union leaders.

In her message, the UN High Commissioner for Human Rights Louise Arbour, stressed that the first and primary leadership call is for governments to step forward and provide the basic human rights guarantees necessary for HIV to be overcome.

In the lead-up to World AIDS Day, UNAIDS worked with the UN Office on Drugs and Crime and the World Bank to produce a report "HIV and Prisons in sub-Saharan Africa: Opportunities for Action."

"While it is well known that sub-Saharan Africa has been hardest hit by the epidemic, little is known about the prison community and HIV," the three agencies said in a joint statement.

In a special gesture, tennis star Roger Federer [Images] who is United Nations Children's Fund Goodwill Ambassador will also star in a World AIDS Day public service.