By Francis Markus BBC correspondent in Shanghai

Health authorities in southern China are reported to be launching a new trial project to supply sterile needles to intravenous drug users to help curb the spread of HIV/Aids.

The scheme, in Guangdong province, bordering Hong Kong, is said to be the first scheme of its kind in China, even though Chinese experts have long been studying projects in other countries.

The United Nations has been warning that China stands on the brink of an explosive Aids epidemic.

Guangdong province, bordering Hong Kong is one of China's most open and outward-looking regions.

So it is not surprising that it is the location for this venture into new and controversial territory.

Health officials, quoted by an official newspaper there, say the trial project to supply sterile needles to drug users will include a campaign to educate addicts about the dangers of HIV/Aids transmission.

Politically sensitive

Although needles are already available for purchase in many Chinese pharmacies, experts say there is widespread ignorance about the infection risk from dirty needles.

They say China has studied needle exchange schemes in other countries before.

But authorities have been unable to overcome the contradiction between the health issues and the law, which requires that drug users be punished.

There have been signs of greater openness in China's handling of the Aids problem, which the United Nations warns is in danger of exploding into a catastrophic epidemic.

But politically, the disease remains a highly sensitive topic. So Aids experts and activists will be keenly watching the Guangdong pilot project to see if it heralds a new, more pragmatic approach.