"Naturally, the problems linked to July 22nd have been widely discussed in the public debate for months but the language used has until now been primarily legalese, journalese and, most recently, psychiatric," Kai Johnsen, the artistic director of the Drama House (Dramatikkens hus) told AFP.

"I think art is also an important voice to understand and decipher the problems" raised by the attacks, he said.

The Drama House therefore aims to stage in October a play currently being prepared by Danish artistic director Christian Lollike, who will also take the role of right-wing extremist Anders Behring Breivik.

Titled "Manifesto 2083" — a reference to the year Behring Breivik thinks his ideology will triumph — the play is expected to be a monologue based on the 1,500-page manifesto the 33-year-old posted online just before carrying out his twin attacks in Norway.

While the first performance is not expected for months yet, Lollike's plans have already been heavily criticised in Denmark.

In Norway, the head of the association of victims, Trond Henry Blattmann who lost his son in the attacks, called the project "incredibly shocking."

"We have nothing against a debate on views on the extreme right. We know that books, films and why not theatre pieces will see the light of day" focusing on the attacks, he said.

"But we cannot accept this project's format with a monologue based on Behring Breivik's writings," he added.

Faced with the criticism, Johnsen insisted on the importance of the future play.

"We have to have the greatest understanding and greatest respect for what the families of the victims and the survivors are going through," Kai Johnsen responded.

"But it was not only an attack against a certain number of people, their families and their friends. It was an attack against society as a whole," he insisted.

Behring Breivik, who has claimed to be on a crusade against multi-culturalism and the "Muslim invasion" of Europe, set off a car bomb outside government buildings in Oslo, killing eight people.

He then went to Utøya island north-west of Oslo, and, dressed as a police officer, spent more than an hour methodically shooting and killing another 69 people, mainly teens, attending a summer camp hosted by the ruling Labour Party's youth wing.