SYDNEY (AFP) - An 18-metre bright pink condom raised eyebrows in Sydney on Friday after it was erected over a Sydney landmark as part of a new awareness campaign about HIV.

The giant sheath was placed over a heritage-listed obelisk at Hyde Park in the centre of the city.

"This installation is sure to create lots of interest as we've selected a very visible icon in a high traffic area," said Nicholas Parkhill from the AIDS Council of New South Wales (ACON) behind the campaign.

Parkhill said while new drugs were able to help in the fight against HIV, the virus which causes Aids, condoms were still crucial in stopping the spread of the disease, particularly among gay men.

"We need to constantly find new ways to promote this message, especially in the lead up to World Aids Day on December 1," he added.

But Wendy Francis from the Australian Christian Lobby said the stunt was disappointing and "inappropriate for open spaces where children can see it", she told Australian Associated Press.

The number of new HIV cases in Australia is at its highest level in 20 years with 1,235 new cases diagnosed in 2013.

The giant condom will be on the obelisk until Wednesday.