Images of a woman saying she feels safer using condoms with her boyfriend were being screened in a 30-second advert on China's main television network ahead of World Aids Day on December 1, the Xinhua news agency said.

Condom ads appeared on the backs of buses and briefly on television in the late 1990s but were then pulled.

"Both were removed after they attracted criticism from residents and were deemed in breach of regulations," Xinhua said. "According to these regulations, advertisements related to sex or obscenity are banned or restricted."

Unsafe sex is now believed to account for some 10 percent of HIV (news - web sites) cases in a country where the sex industry has exploded alongside economic reforms introduced since the late 1970s.

China, which only faced up to its AIDS epidemic a couple of years ago, has stepped up its battle against the disease in recent months by pledging free drugs to poor people suffering from HIV, the virus which causes AIDS.

But many questions remain over whether the government's campaign is translating into real aid for China's official tally of 840,000 HIV sufferers and 80,000 AIDS victims -- many of whom were infected by blood-selling schemes in the central regions.

Beijing has long been under fire for disguising the scale of the HIV/AIDS epidemic and rounding up AIDS activists.

Experts estimate the real number of Chinese HIV sufferers could be closer to 1-1.5 million and say that could easily jump to 10 million or more by 2010.