Bob Dylan's artwork is going on display at the National Portrait Gallery.

A dozen new pastel portraits will go on show from August 24 in an exhibition, Bob Dylan: Face Value, at the London gallery.

The singer-songwriter has sketched and drawn since childhood and began to paint in the 1960s. He first exhibited his work six years ago. His latest pastel portraits have not been shown anywhere before.

The portraits are "an amalgamation of features the musician has collected from life, memory and his imagination and fashioned into people".

Gallery director Sandy Nairne said: "Bob Dylan is one of the most influential cultural figures of our time.

"He has always created a highly visual world either with his words or music, or in paints and pastels."

Art historian John ­Elderfield, who helped bring the display to the Gallery, said the paintings were the "products of the same extraordinary, inventive imagination" behind Dylan's songs.

In 2008, London's Halcyon Gallery featured Dylan's drawings and sketches from periods on the road.