Psychiatrists in Norway are due to submit their assessment of whether Anders Behring Breivik was sane at the time he killed 77 people last July. Their 230-page report - said to be based on 13 conversations with Breivik - will be delivered to a court in Oslo. It will determine whether Breivik can claim an insanity defence when he stands trial on 16 April. He has admitted the attacks in Oslo and on the island of Utoeya, but has pleaded not guilty to terror charges. At earlier hearings, the 32-year-old sought to justify the carnage by saying it was \"necessary\" to save Norway and Europe from Muslims and multiculturalism. The 22 July attacks - which also injured 151 people - traumatised the nation. Breivik has admitted that, disguised as a police officer, he planted a car bomb that exploded close to government offices in the capital Oslo, killing eight people. He then drove to the island of Utoeya, where a summer youth camp of Norway\'s ruling Labour Party was being held. In a shooting spree that lasted more than an hour, he killed 69 people - mostly teenagers. Breivik made his first public appearance in court earlier this month, in front of his victims\' families, survivors of the attacks and reporters. He told the court he was \"a military commander in the Norwegian resistance movement\", before the judge interrupted him. The prosecutor\'s office is expected to reveal the conclusions of the psychiatric report at a news conference later.