The report by the July 22 Commission was prepared at Stoltenberg's request and released Tuesday. Anders Behring Breivik, who is awaiting a court decision on his sanity, set off a car bomb outside the prime minister's office in Oslo that killed eight people and then gunned down 69 people, mostly teenagers, at a camp for young people run by Stoltenberg's Labor Party at a lake near the capital.
The report blamed Stoltenberg for seven years of wrangling about whether to close a street in front of the building where his office is located, The Christian Science Monitor reported. Experts had said the office was vulnerable to a car bomb.
The commission found a 2007 Stoltenberg memo saying closing the street was not a high priority.
Now, Per Sandberg, deputy leader of the Progress Party, is calling for Stoltenberg's ouster. Verdens Gang, the country's biggest newspaper, and families of some of the young people who were killed in Breivik's shooting rampage also say the prime minister must go.
Stoltenberg has called for a special meeting of Parliament where he will present his plans for putting the commission's recommendations into place.