Anders Behring Breivik demanded that Norway's government resign and King Harald V abdicate before he would reveal more about his confessed bombing and shooting spree that killed 77 people, Norwegian public broadcaster NRK reported.

The 32-year-old rightwing extremist also called for the resignation of the Norwegian military's top brass and demanded that he be named head of the army during an interrogation on Friday -- his second since the July 22 massacre, NRK reported late Saturday.

But although his demands were categorically denied, the man who has confessed to killing eight people in a bombing of government offices before shooting another 69 at a youth summer camp, finally cooperated during the 10 hours of questioning.

In an interview with AFP Saturday, Norwegian police prosecutor Paal-Frederik Hjort Kraby said Behring Breivik had been "very willing to talk," with one exception: divulging the other "cells" of the organisation he previously had claimed to be a part of.

Behring Breivik is being held in isolation at a high-security prison, and his detention is set to be reexamined every eight weeks.

Two psychiatrists are set to begin assessing this week whether he is legally insane, as prosecutors seek to bring him to trial next year, and are expected to report back by November 1.

His lawyer Geir Lippestad said last week that his client was most likely insane, although he said it was too soon to say whether that would be the line of his defence.