The New Zealand Aids Foundation says the Pope's easing of his stance on the use of condoms is extraordinary and significant.
The teaching of the Roman Catholic Church is that the use of condoms is sinful because they are a form of artificial contraception.
But in a series of interviews with German Catholic journalist Peter Seewald earlier this year and publised in the Vatican newspaper, the Pope endorses the use of condoms in some instances.
Pope Benedict says the use of condoms can sometimes be justified, for example, when used by a male prostitute to reduce the risk of HIV infection and the spread of Aids.
His comments are due to be published soon in a book.
New Zealand's Aids Foundation executive director Rachael Le Mesurier says the comments are phenomenal in the run-up to World Aids Day on 1 December.
She says Catholic populations overseas have been compromised by poor leadership by the Pope and believes it is one of the Church's most significant announcements in hundreds of years.
Ms Le Mesurier says it is wonderful the Pope is beginning to realise that condoms work to prevent HIV transmissions.
Other campaign groups around the world working to combat the spread of HIV and Aids have also welcomed the Pope's remarks.