File photo: A man looks at the drawing El Virgo by Pablo Picasso, part of the exhibition Secret Imagenes at the Museo Picasso in Barcelona.

Barcelona - An unknown drawing that appears to be the work of Pablo Picasso (1881-1973) has been discovered at the Picasso Museum in Barcelona, its representative said on Monday.

The drawing, which has been named “Figure with pipe,” had been attached to the back of Picasso's 1896 painting “Portrait of the mother of the artist.”

It was discovered when the painting was restored.

The drawing, which appears to copy some 18th-century Flemish engraving, was made before the painting. It may have been an exercise forming part of Picasso's artistic training, museum director Bernardo Laniado-Romero said.

“Portrait of the mother of the artist” had been donated to the museum by Picasso in 1970.

The drawing presents similarities with another drawing dating from Picasso's formative years. Experts at the museum were working on confirming whether it had indeed been made by the artist. - Sapa-dpa