Puer gold for makers of Posh's weight-loss tea as China outlaws copycats.

As Champagne can only come from that region of France so Puer Tea will soon only be able to come from Yunnan Province in China.

The decision is as controversial as the Champagne ruling and according to the China Daily will cause the closure of dozens of tea factories.

At the heart of the debate about this tea – which is drunk by Victoria Beckham as a weight loss aid – is what exactly can be called Puer tea, with the two major producers - Yunnan and Guangdong provinces - battling it out for their economic future.

The background is a decision taken late last year by China’s General Administration of Quality Supervision, Inspection and Quarantine. It introduced a national standard stating that only tea produced in Yunnan's 639 towns in 11 prefectures and cities, including Puer and Dali, can be called Puer tea.

It also banned the sale of Puer tea not produced or processed in the area after June 30 this year and stipulated that the tea can only be made from a large leaf variety of the plant growing in the defined area that is then processed using a specified technology.

According to the standard, except for those 639 towns, other locations such as Guangdong, cannot call its tea Puer. Guangdong province will then be stripped of the right to process and sell tea that carries the name.

The controversy is partly because of the long history of Puer tea in Guangdong. A recent paper by Prof Ding Junzhi from South China Agricultural University says that Guangdong was one of the earliest places to process Puer tea. All this has seen the Guangdong Tea Procession Association mount a fight-back to try to change minds.

Xiaguan Te Ji (Special grade) raw tuo cha from 2005

Historically the tea is traditionally made with leaves from old wild tea trees of a variety known as broad leaf tea or Camellia sinensis var. assamica, which is found in southwest China as well as the bordering tropical regions in Burma, Vietnam, Laos and the eastern parts of India.

It is well known for the fact that it is a compressed tea and also that it typically ages well to produce a pleasant drink, much like a fine wine.

Often the leaves are compressed into tea cakes or bricks, and are wrapped in various materials, which when stored away from excessive moisture, heat, and sunlight help to mature the tea.

It has medicinal qualities, which include helping in the reduction of cholesterol in the blood stream, in the reduction of body weight and in the reduction of high blood pressure.