Breivik planned to behead former Prime Minister

Anders Behring Breivik is watched by his lawyer Geir Lippestad (EPA)

The self-confessed mass killer Anders Behring Breivik yesterday boasted about his plans to behead Norway's revered former prime minister, Gro Harlem Brundtland, and post a video of her decapitation on the internet.

As Breivik, 33, gave evidence on the fourth day of his trial in Oslo, it also emerged that he "trained" for the attacks of July last year by playing the war simulation computer game Call of Duty: Modern Warfare, which he used to practice his shot. He has admitted killing eight people by detonating a bomb in the capital and shooting dead 69 mostly teenage victims at a Labour Party youth camp.

Breivik told the court he had planned to capture Mrs Brundtland, a respected international figure and leading member of Norway's ruling Labour Party who served as the country's first and only woman prime minister during the 1980s. "The plan was to behead Gro Harlem Brundtland on film," he said.

Mrs Brundtland had been a guest at the Labour Party youth camp on Utoya island only hours before Breivik arrived in a police uniform on 22 July and began shooting dead young party members. Breivik said Mrs Brundtland had been a key target. However, she was ferried off the island shortly before his arrival.

The right-wing extremist, who has claimed he was part of a crusade against "Marxist multiculturalism" and the "Islamification" of Europe said he had been inspired by the beheading techniques used by al-Qa'ida to intimidate its opponents.

He also revealed that he had intended to kill all of the nearly 600 young socialists attending the Utoya camp: "The goal was not to kill 69 people on Utoya. The goal was to kill them all," he said.

Breivik also told the court that his original plan had been to set off three bombs in Oslo, which would have included the Labour Party headquarters and possibly the Royal Palace as additional targets. He conceded that he had restricted himself to making one bomb because the process was more difficult than he thought.

On the first three days of his trial, Breivik entered the courtroom and punched the air with a clenched fist Nazi-style salute. Yesterday he agreed to stop making the salute following complaints from relatives of his victims

Breivik had said the gesture was a greeting used by the fanatical so-called "Knights Templar" crusader organisation of which he claims to be a member. The prosecution says it does not believe the group exists. Judges have yet to decide whether Breivik is insane or fully responsible for his actions. Psychiatrists are divided over the issue.