It is the dream of many artists to paint for a nation's leader. Gao Dongsheng has done it more than once. He has created works for Chinese leaders Deng Xiaoping and Jiang Zemin, and former British prime minister Margaret Thatcher. But Gao's canvas is one of the most demanding imaginable: he paints the inside of tiny snuff bottles. Gao, 39, is one of the few remaining masters of the art which dates back to the late Ming dynasty (1368-1644), and involves painting through the neck of the pocket-sized crystal and glass bottles with ultra-fine brushes to depict traditional Chinese scenes, landscapes or portraits. An artistic streak runs through the Gao family. 'My grandfather was a painter,' he says. 'And I made sketches, oil paintings and studied calligraphy.' At the age of 18, Gao fell in love with snuff bottle painting after discovering the work of master Liu Shouben in a Beijing arts and crafts factory. 'I wanted to learn from him. Few people made this art. I found it very meaningful. Once masters only taught their own children, but after the liberation , the nation wanted them to teach others so that the art would not be lost,' he says. More than 500 people sat a job application test, but only 10 were taken on. Gao was one of them. And he soon learned just how difficult this rare art was to achieve. Painting on a canvas or paper is straightforward enough, but having to illustrate the inner surface of a tiny curved bottle is a different matter. 'My hand shook when I held the brush inside and I couldn't paint accurately. My eyes were very tired. The objects in the painting were very small. For instance, I had to paint 100 children and their eyes, I couldn't see them and had to paint by feel,' he says. 'I failed many times and had to polish off the paint. Some bottles were polished so much that they broke.' But Gao persevered and picked up the basics of the art in three months. Every day he worked alongside his master, earning a low salary and no recognition. As he became better known, important people started asking him to paint bottles for them - including late paramount leader Deng. 'I got an order from the Beijing city government in 1990. They passed me a picture of him in his 70s and asked that I paint his portrait in a bottle,' he says. It was not too difficult to paint Deng who, he recalls, had a pinkish complexion. But Gao was not too excited about landing the job. 'I try my best in completing every piece, not just because he is a leader,' he says. He was also commissioned to work for recently retired leader Jiang, the late Kuomintang general Zhang Xueliang and many other premiers, including Thatcher, and the queen of Denmark. In 1995, he began exhibiting around the world and earned many awards, including being singled out by Unesco as a 'Chinese Folk Arts and Craftsman'. His works - some fetching more than $10,000 - have attracted international collectors. Sitting in his booth in a quiet corner on the second floor of Cityplaza in Taikoo Shing - where he is part of the Chinese Art and Cultural Expo that runs until Sunday - Gao paints names inside bottles which can be purchased for $20. 'I have bought bottles for myself and my brother,' says one old man, as others discuss the beauty and intricacy of the art form. However, few realise that the works on display are those of Gao's students. His own bottles, including one with a Chinese general issuing orders and another featuring six women, each with a different expression, are displayed on a special shelf. From his Beijing workshop, he has produced more than 1,000 snuff bottle paintings over the years. But are they more than merely merchandise to him? 'I still feel heartbroken when I sell a piece,' he says. Hoping to keep the art form alive, Gao is kept busy teaching others. His daughter will study the technique when she turns 15 in two years' time. What keeps him so devoted to such an exhausting and exacting craft? 'I just love it. And I won't stop until my eyesight fails or my hands are no longer steady.'