Papua New Guinea's outgoing health minister, Sir Peter Barter, says new figures showing a decrease in the prevalence of HIV are unrealistic.
Estimates by government health agencies and overseas partners show an HIV prevalence rate among adults aged 15 to 49 years of just under 1.3 percent.
Sir Peter says while the new data is better than any previous data collected, it was taken over too few testings to produce a realistic figure.
He says the rate could be as high as three percent.
"The actual figures that we've been able to obtain through fairly accurate means over the limited number of people being tested comes down to 1.28, which unfortunately whilst it sounds good because it's lower than the 1.7 that's been commonly thought - we don't believe that the figures are, in reality, true because we need to do a lot more testing."
Sir Peter says the new figures show the prevalence rate is levelling off in urban areas but spiralling in rural areas.