Anders Breivik has refused to give details about his visit to London 10 years ago, during which he claimed an anti-Islamic organisation called the Knights Templar was founded.
Questioned by prosecution on whether he met fellow anti-Islamic activists including a character named 'Richard The Lionheart' in London in 2002, as detailed in his notorious manifesto, Breivik said there was a meeting but was evasive about the exact details.
"It is not in my interest to shed light on details that could lead to arrests," he told the Oslo court on Wednesday.
"There is nothing that is made up, but you have to see what is written in a context. It is a glorification of certain ideals," Breivik said in relation to his manifesto.
But he was warned by the judge that a refusal to give details in response to questioning could be used against him.
Prosecutors showed images of Breivik taken from his manifesto. A badge on the uniform read "Marxist Hunter"
Appearing on the third day of his trial for the murder of 77 people in July last year, the 33-year-old did not discuss claims in the document about his "English protestant host" and the founding session of the Knights Templar group.
Prosecutors have said they believe no such organisation exists.
While the killer's credit card was used in London at the time, it is not clear he met with any fellow activists.
An EDL member who blogs under the name "lionheart" has previously denied meeting Breivik.
Breivik told the court on Tuesday said he "would do it all again because he was motivated by goodness, not evil."
During the trial he told the judge: "I do not recognise the Norwegian courts"
The far-right extremist said his bombing campaign and shooting spree was the "most sophisticated and spectacular political attack seen in Europe" since World War II.
The killer wipes away a tear as the court sees his propaganda video
The killer's 30-minute testimony was not broadcast so as not to give a platform to his extreme views. However press were allowed to stay in court and report his views, and his full statement will be available later.
As Breivik has admitted to the Oslo car bomb and shooting in Utoya, the trial is likely to focus on whether or not the killer is sane. His defence team have said the extremist would like to be found legally sane.