The connection emerged following scrutiny of Breivik's links to Briton Paul Ray who writes a blog under the name Lionheart.
Ray has denied meeting the Norwegian gunman but admitted that he may have drawn "inspiration" from his writings.
Ray played host to Johnny 'Mad Dog' Adair - a former leader of the UDA's notorious 'C company' on Belfast's Shankill Road - in Malta last February.
He is also friends with Nick Greger, a German known as 'Nazi Nick' who describes himself as a "former neo-Nazi leader".
Adair, Ray and Greger appear together on a YouTube video titled 'The Gathering'.
The film shows the three men visiting churches around Malta, cut together with footage of loyalist terrorists and Mr Greger with a Kalashnikov.
It has been widely reported that in postings Breivik made on British nationalist websites and in the manifesto released before the attacks he refers to a "mentor".
Parallels have since been drawn with Ray, who leads an anti-Islam Knights Templar movement, but he strongly denies having anything to do with the attacks.
In his manifesto, the Norwegian guman Breivik claims allegiance to a resurrected version of the Knights Templar, a medieval formation of Christian soldiers who waged brutal battle against Islam. The Oslo killer claims he attended the founding meeting of the 'Knights Templar Europe' explaining that he “joined the session after visiting one of the initial facilitators, a Serbian Crusader Commander and war hero, in Monrovia, Liberia.”
In his 1,500-page document Breivik wrote that his 'assigned mentor' at the London meeting was “referred to as Richard (the Lionhearted).”
Ray said he was not at the 2002 London meeting that Breivik describes in his manifesto.
Referring to the right-wing British group the English Defence League, Breivik added: “I wonder sometimes if one of the EDL founders was one of the co-founders of [the Knights Templar], I guess I’ll never know for sure.”
Ray, who the Associated Press located in Malta, where he now lives, confirmed the existence of a loose group of anti-Islamic extremists inspired by the Knights Templar.
The 35-year-old Briton often, who was a founding member of the EDL, espouses views similar to Breivik's on his anti-Muslim blog. The blog's title is a reference to King Richard I of England, who led Christian crusades in the 12th century and was known as Richard the Lionheart.
Ray has other similarities with the "mentor" in the Norwegian killer's manifesto, chiefly that the anti-Muslim group he leads is called The Ancient Order of the Templar Knights.
Ray suggested the group had no formal structure, and he refused to name any members or indicate how many members it has. He said he condemned Breivik's attacks in Norway.
"It's an idea," Ray said. "It's not like it's a massive organization. It's a belief."
Ray condemned the murder of 76 people in twin attacks in Oslo and Utoya on Friday as an act of "pure evil".
Ray, 35, told The Times: "I am being implicated as his (Breivik's) mentor. I definitely could have been his inspiration. It looks like that. But what he did was pure evil. I could never use what he has done to further my own beliefs. What he has done does not equate to anything I am involved in."
Breivik, 32, claims he committed Friday's massacre as the order's first blow in an apocalyptic war against Muslims, immigrants and leftists to prevent what he believes is an Islamic attempt to take over Western Europe. In his manifesto he says he is a member of a new order of the Knights Templar.
The European police agency Europol said it is investigating links between Breivik and right-wing groups in Europe.
A task force was set up shortly after the Norway attacks to help in the probe but a Europol spokesman said British police would also join the task force.
Excerpt from Anders Breivik's manifesto
"I am the Norwegian delegate to the founding meeting in London, England and ordinated as the 8th Justiciar Knight for the PCCTS, Knights Templar Europe. I joined the session after visiting one of the initial facilitators, a Serbian Crusader Commander and war hero, in Monrovia, Liberia.
"Certain long term tasks are delegated and I am one of two who are asked to create a compendium based on the information I have acquired from the other founders during our sessions. Our primary objective is to develop PCCTS, Knights Templar into becoming the foremost conservative revolutionary movement in Western Europe the next few decades.
"This in relation to developing a new type of European nationalism referred to as Crusader Nationalism. This new political denomination of nationalism will become the foremost counterweight to National Socialism and other cultural conservative political denominations, on the cultural right wing.
"Everyone is using code names; mine is Sigurd (the Crusader) while my assigned mentor is referred to as Richard (the Lionhearted). I believe Im the youngest one here."
Ray denies links to Breivik
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