On the occasion f world AIDS day, the US president Barack Obama has urged the global community to step up efforts to defeat the epidemic once and for all.

He also appealed to the US Congress, drug companies and state governments to re affirm their commitment to end the disease. "Make no mistake, we are winning this fight -- but the fight is not over, not by a long shot," Obama said while speaking at an event marking the day.

The president also announced an additional $15 million of funding for a program that supports HIV medical clinics in the US and an additional $35 million for state AIDS drug assistance programs.

Obama was joined by Bill Clinton, who participated in the event by phone and George W Bush, who spoke from the African nation of Tanzania alongside the country's President, Jakaya Kikwete.

Even as there is optimism and praise for the efforts to combat AIDS, there are huge concerns over budget cuts in funding for fighting AIDS due to the global economic slowdown. The Global Fund has announced its decision to call off the latest round of funding to Fight Aids, TB and Malaria.

Several countries around the world are cutting their aid budgets amid global financial crisis. The cancellation of the 11th annual round of funding means that the new applications will not be accepted by the year 2014. The Global Fund, which is a joint initiative between the public and private enterprises, is the single largest donor for HIV funding in the world. It provides more than 70 per cent of the money for antiretroviral drugs in developing nations.

"At a time when so much in Washington divides us, the fight against this disease has united us across parties and presidencies. It has shown that we can do big things when Republicans and Democrats put their common humanity before politics. Let's carry that spirit forward," Obama added.