The father of Norwegian right-wing extremist Anders Behring Breivik, who killed 77 people in twin attacks in July, says his son is the "worst terrorist" since World War II, in an interview released on Wednesday.

• Police lost 16 minutes going to Utøya: report (16 Dec 11)

Jens Breivik, 76, a retired diplomat who lives in the south of France, told German news weekly Stern that he last had contact with his son about six years ago by phone but that he now wanted to visit him in prison.

"I want to look him in the eyes. Perhaps I am in a position to arouse feelings in him," he told Stern in comments published in German.

"He is the worst terrorist since the Second World War. He killed 77 innocent people and isn't even showing remorse," he added in an interview.

Breivik, who divorced Anders's mother when he was one year old, said they did not have much of a father-son relationship and had no common interests. But he indicated he felt a sense of guilt.

"Probably all that wouldn't have happened if I had looked after Anders more," he added.

Behring Breivik killed a total of 77 people on July 22nd, most of whom died when he embarked on a shooting spree on the island of Utøya, some 40 kilometres north-west of Oslo.

He had earlier set off a car bomb outside government buildings in Oslo, killing eight people.

His father had worked in one of the now destroyed government buildings in the 1990s, Stern said.

Now in custody at the high-security Ila prison near Oslo, Behring Breivik, 32, is scheduled to go on trial on April 16th.

A psychiatric evaluation of the confessed killer who claimed to be on a crusade against multiculturalism and the "Muslim invasion" of Europe, concluded late last month that he suffered from "paranoid schizophrenia".

If confirmed by a panel of experts and the Oslo court, that conclusion will most likely mean Behring Breivik cannot go to prison but instead will be sent to a closed psychiatric institution for treatment.