Experts on HIV-AIDS gathered in Vancouver are calling on political leaders worldwide to take action to help end the global epidemic.

International AIDS Society president Chris Beyrer said community organizers have reached a consensus on asking world leaders to commit to giving all people diagnosed with HIV immediate treatment.

Dr. Julio Montaner, director of the B.C. Centre for Excellence in HIV-AIDS, said science has clearly proven that giving people with HIV early access to treatment saves lives.

"It is now irrefutable. There is no discussion anymore. The science is all in," he said on Sunday. 

New data will be unveiled in Vancouver at the 8th International AIDS Society (IAS) Conference on HIV Pathogenesis, Treatment and Prevention, which began on Sunday and runs until Wednesday.

More than 6,000 international experts are attending the Vancouver conference, and Montaner said they all need to have the same message when it comes to pressuring governments to support HIV treatment.

"We need to come out of this conference with a single voice because we have now the unique opportunity of ending the epidemic."

The conference will draw a line in the sand between people who are committed to ending the HIV/AIDS epidemic — and those who aren't, Montaner said.

"Political leaders of the world, you are either with us or against us. We know the evidence, we know what needs to be done. It is up to you to decide whether you will be counted as doing the right thing."