Two professional art restorers were brought in from Prague, who spent ten days scraping away 20 layers of paint with scalpels to reveal the picture.
The works depicts five life-sized soldiers with machine guns, smiley faces, and wings alongside the slogan “Every picture tells a lie!”
Banksy painted the picture during a graffiti festival called “Backjumps” held in the arts centre in 2003. It has now been brought to light by Brad Downey, a US artist who was also part of “Backjumps,” and who was asked to design the room for a new exhibition at the Bethanien entitled “Do not think!”
Adrian Nabi, the curator who originally invited Banksy to Berlin, is also responsible for the new exhibition.
Speaking to Berlin newspaper Der Tagesspiegel, Downey described the work on the room as a journey back in time to when street art was less commercialized.
Banksy, who eventually became the world's most well-known street artist, travelled around the world using stencils to spray his works on walls in Britain, Israel, Mexico and the US.
He also came to Berlin several times, and some of his works can still be found in the Kreuzberg and Mitte districts of the German capital. Most of them have since been painted over, though many of those that weren't, have been sold for several thousand euros.
It is unclear what will happen to the work in the Bethanien arts centre, though Downey simply told the paper, “Maybe it will just be painted over again.”