With brushes and a paint-splotched palette, Chinese artist Yang Feiyun adds the finishing strokes to his latest work - a portrait of the moustached 17th century Spanish King Felipe IV.

An untrained eye would fail to tell the difference between Yang's canvas and the original by the Spanish master Velazquez, hanging inches away in a crowded gallery at Madrid's Prado Museum.

"I have been painting my whole life, ever since I was a child, and Velazquez is a master among painters. He is known in China for his great depth," Yang says.