"Ifwe accelerate a scale-up of all HIV services by 2020, we will be on track to end the epidemic by 2030," said Sidibe.

"If not, we risk significantly increasing the time it would take, adding a decade, if not more," he added.

Francoise Barre-Sinoussi said: "Some 22 million people still do not have access to treatment. The official AIDS 2014 theme reminds us that we need to step up the pace and redouble our efforts.

"Too many countries are still struggling to address their HIV epidemic, with their most vulnerable people consistently being left behind," she said.

According to conference organizers, AIDS 2014 will feature programs with presentations around topics including HIV cure strategies and challenges, HIV prevention strategies, and tuberculosis and hepatitis C co-infection.

Some 12,000 participants from all over the world have gathered at the conference under the theme Stepping up the Pace.

Contact thewriter at shanjuan@chinadaily.com.cn