South African President Jacob Zuma vowed on Thursday to strengthen the fight against AIDS in the world's worst affected country, in a "renewed onslaught" against the epidemic.

"We are not yet winning this battle," Zuma said in his annual address to the second house of parliament.

"We need to do more, and we need to do better, together. We need to move with urgency and purpose to confront this enormous challenge," he said.

"If we are to stop the progress of this disease through our society, we will need to pursue extraordinary measures."

He said an announcement would be made on December 1, World Aids Day, on additional measures to counteract the "chilling statistics" of deaths of young people.

Zuma cited statistics showing that six out 10 deaths in 2006 were among people younger than 50 years, while the overall number of deaths in 2008 jumped to 756,000, up from 32 percent from the year before.

"Let us resolve now that this should be the day on which we start to turn the tide in the battle against AIDS."

"If we do not respond with urgency and resolve, we may well find our vision of a thriving nation slipping from our grasp."

After becoming an international pariah for its policies of denial under former president Thabo Mbeki and his health minister Manto Tshabalala-Msimang, South Africa made a dramatic turn around, pledging to cut new infections in half by 2011.