Breivik also announced he doesn't recognize the authority of Judge Wenche Elisabeth Arntzen, because he said she is friends with the sister of former Norwegian Prime Minister and Labor Party leader Gro Harlem Brundtland.
The anti-Muslim militant described himself as a writer, currently working from prison, when asked by the judge for his employment status.
He claims he targeted the government headquarters in Oslo and the youth camp to strike against the left-leaning political forces he blames for allowing immigration in Norway.
If deemed mentally competent, Breivik would face a maximum prison sentence of 21 years or an alternate custody arrangement under which the sentence is prolonged for as long as an inmate is deemed a danger to society.
Breivik wants to be judged as a sane person and will call radical Islamists, and extremists on the right and left to testify to support "his perception that there is a war going on in Europe," his defense lawyer, Geir Lippestad, told the court. Lippestad said Breivik wants to read a new document he's written at the start of his testimony on Tuesday.
While Norway has a legal principle of preventive self-defense, that doesn't apply to Breivik's case, said Jarl Borgvin Doerre, a legal expert who has written a book on the concept. "It is obvious that it has nothing to do with preventive self-defense," Doerre told The Associated Press.
Police sealed off the streets around the Oslo court building, where journalists, survivors and relatives of victims watched the proceedings Monday in a 200-seat courtroom built specifically for this trial.
Thick glass partitions were put up to separate the defendant from victims and their families, many of whom are worried that Breivik will use the trial to promote his extremist political ideology. In a manifesto he published online before the attacks, Breivik wrote that "patriotic resistance fighters" should use trials "as a platform to further our cause."
After he surrendered, Breivik had told investigators he is a resistance fighter in a far-right militant group modeled after the Knights Templar a Western Christian order that fought during the crusades. Police, however, have found no trace of any organization and say he acted alone.
"In our opinion, such a network does not exist," prosecutor Svein Holden told the court on Monday.
In his manifesto, Breivik described the supposed group's initiation rites, oaths and the "clenched fist salute" that he used in court, symbolizing "strength, honor and defiance against the Marxist tyrants of Europe."
After blowing up parts of the government building and shooting dozens to death on Utoya island, Breivik surrendered to police 1 hour and 20 minutes after he arrived on Utoya. The police response to his terror spree was slowed by a series of mishaps, including the lack of an operating police helicopter and the breakdown of an overloaded boat carrying a commando team to the island.
Breivik called police twice, saying he wanted to turn himself in. In one of the calls, played in court Monday, he identified himself as a commander of "the Norwegian resistance movement" and said he had "just completed an operation on behalf of Knights Templar."
When the operator asked him to repeat himself, Breivik sounded irritated and hung up.