Anders Behring Breivik, who has admitted to killing 77 people in Norway last year, says he wants the court either to acquit him or impose the death penalty.
Norway does not have the death penalty, and Breivik denounced the 21-year maximum sentence as "pathetic."
Breivik was testifying in the third day of his trial in the Norwegian capital.
Prosecutors asked him about his contacts with militant nationalists abroad and about the Knights Templar movement of which he claims to be a member.
He refused to provide details and accused prosecutors of "trying to sow doubt" about the network and of "ridiculing" him.
He also warned Norway could be attacked by two other "cells" of militant nationalists.
Earlier he described the Knights Templar as "a group of self-sufficient, one-man cells."
His testimony is not being broadcast for fear he will use the trial to propagandize his extremist views.
During his first day of testimony on April 17, Breivik described his bomb attack and shooting spree as "sophisticated and spectacular" and said he would do the same thing again.
He called the attack a "legitimate defense" against multiculturalism, saying it was "cruel, but necessary."
The court has allotted 5 1/2 days for Breivik's testimony.
If convicted and found sane, he faces up to 21 years in prison, a term that could be extended.
If judged insane, he could be committed to psychological treatment indefinitely.
Based on reporting by AFP, dpa, and AP