Oslo Anxious to prove he's not insane, confessed mass killer Anders Behring Breivik told a court yesterday that questions about his mental health are part of a racist plot to discredit his extreme anti-Muslim ideology.

Breivik, who has admitted to killing 77 people in a bombing and youth camp massacre, said no one would have asked for a psychiatric examination had he been a "bearded jihadist".

"But because I am a militant nationalist, I am being subjected to grave racism," he said. "They are trying to delegitimise everything I stand for."

Breivik rejects criminal guilt for the rampage on July 22, saying the victims had betrayed their country by embracing immigration.

Even the defence admits there is virtually no chance of an acquittal, so the key issue to be determined in the trial is whether Breivik is criminally insane. Two psychiatric examinations reached opposite conclusions on that point.