The world’s dwindling population of tigers could be pushed closer to extinction after China quietly approved the sale of products extracted from the endangered animals.

Environmentalists warned yesterday that the move could boost trade in illegal potions and create a market for poachers preying on the rare animals as far away as India.

Tiger tonics, such as wine made from ground bones, are regarded as potent traditional Chinese medicines and fetch a high price on the black market.

The Chinese State Forestry Administration, which is responsible for wildlife, issued a document allowing trade in legally obtained tiger and leopard skins in December 2007, but with such little fanfare that it barely rated a mention in the domestic media.

Almost every reference was subsequently erased from the internet, apparently amid official concerns of damage to China’s reputation before the 2008 Olympics in Beijing.

The alarm was sounded yesterday by Traffic, a wildlife trade monitoring network linked to the WWF. A Traffic official said that the wording of the document was loose enough to allow its possible interpretation by the vast tiger farms in China as a go-ahead to make tiger bone wine.

The document specifies the trade and use of tiger and leopard skins “and their products”. Such pelts are traditionally prized among Tibetans to embellish robes for ceremonial occasions. But it is the three vague words that have sparked anxiety.

Xu Hongfa, of Traffic, said: “I think these words could be used as a cover by tiger farmers to make tiger bone wine and they would try to argue that it doesn’t just refer to skins.”

Only about 30 to 40 tigers survive in the wild in China. But about 5,000 live in tiger farms, where they are bred at great speed. Ostensibly the farms are tourist attractions but it is widely believed that their owners hope to use the animals to produce expensive tiger tonics. The income from visitors to the farms would be dwarfed by the profits from sales of tiger bone wine.

India boasts the world’s largest population of tigers in the wild. Indian conservationists believe that the rapid decline in tiger numbers in the country is a direct result of China’s economic rise and the related increase in demand for traditional medicines. The Indian tiger population stood at 1,411 in February last year, according to an official count, down from 3,642 in 2002 and an estimated 40,000 a century ago.

Ashok Kumar, of the Wildlife Trust of India, a conservation organisation, said that any relaxation of Chinese rules would have a catastrophic effect on the Indian tiger population.

“In all our communications with the Chinese we have been led to believe that the ban is firmly in place,” he said. “We were not aware of this document, [which] could have a huge effect on wild tigers in India by stimulating demand for medicines in China.”

It is also feared that the release of legal farmed tiger products would create a niche market for wild tiger products sourced from India, which would be likely to be regarded as more potent by Chinese consumers and so command a premium.

Conservationists also believe that Indian tigers will be targeted because poaching the animals is much cheaper than farming them. “You can kill a tiger with a few rupees’ worth of pesticide,” Mr Kumar said. “Raising one in captivity is a costly exercise.”

Poachers in India are paid as little as 400 rupees (£5) for a tiger by traffickers who transport the carcasses to China, usually through Nepal.

Tigers have been used for medicinal purposes in China for thousands of years and a single animal can be worth a fortune. The bones are the most valuable part, with the 25kg (55lb) from an average animal worth about 2.4 million yuan (£215,000), many times the price of a skin.

The Indian Government said last week that it was sending a delegation to China to discuss the plight of the sub-continent’s tigers.

Indian officials say that Chinese co-operation is essential if tigers are not to be consigned to history books and zoos. They cite other trades in illicit products, such as drugs, where vast amounts of state funding around the world have made little impact.

“Unless the user co-operates, it will be impossible to stop the trade in tigers,” Mr Kumar said.

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