Hidden painting found under Pablo Picasso masterpiece

The mystery bearded man in the portrait is unknown to experts. Credit: AP

A secret portrait of an unknown man in a bow-tie has been discovered beneath one of Pablo Picasso's first masterpieces 'The Blue Room'.

Scientists used infrared imagery to unveil the mystery bearded man resting on his hand, with three rings on his fingers, wearing a jacket and a bow-tie.

Art experts have ruled out the possibility of a self-portrait but are now investigating who this man could be and why Picasso painted him.

It is a mystery that is fueling new research about the 1901 painting created in Picasso's early career while he was working in Paris at the start of his distinctive blue period of melancholy subjects.

Experts are investigating who the man in the portrait might be and why he was painted by Picasso. Credit: AP

Conservators revealed their findings for the first time last week after a technical analysis confirmed it was likely to have been painted "just before The Blue Room,” curators said.

The revelation of the man's portrait beneath the painting is not the first finding in Picasso's works.

Hidden pictures have been found under some of the artist's other creations, including a portrait of a mustached man beneath the painting 'Woman Ironing', at the Guggenheim Museum in Manhattan.

Picasso's The Blue Room painted in 1901. Credit: AP

Conservators long suspected there might be something under the surface of The Blue Room, judging by the way it was painted.

The Blue Room has been part of the Phillips Collection museum in Washington since 1927 and is on a tour to South Korea until early 2015 as the research continues.

Read: Self-portrait verified as a Rembrandt after months of scientific analysis