Reuters/London

The Quilliam Foundation, a counter-extremism think-tank which said it had brokered the move, hailed it as a big success for community relations but one expert on the far-right warned it could lead to further violence.

Tommy Robinson was the most prominent figure in the English Defence League (EDL), which has staged numerous high-profile street protests across Britain since 2009, often in mainly Muslim areas. Many protests have led to violence.

“I have been considering this move for a long time because I recognise that, though street demonstrations have brought us to this point, they are no longer productive,” Robinson said. “I acknowledge the dangers of far-right extremism,” he said in a statement.

Quilliam said Robinson’s associate Kevin Carroll had also quit the EDL but he could not be reached for comment.

To their foes, the EDL is made up of soccer hooligans and racists, representing a dangerous, far-right ideology. Their supporters say their views echo the concerns, ignored by politicians, of many Britons about immigration and the rise of preachers who support terrorism and are to blame for attacks such as the deadly 2005 London suicide bombings. The EDL was formed by Robinson, whose real name is Stephen Lennon, in Luton, a town 55km north of London, after a small group of Islamists staged a noisy protest during a homecoming parade by British soldiers from Afghanistan.

Since then the EDL has held numerous protests, attracting several hundred to a few thousand supporters, which have led to clashes with police, anti-fascist groups, and Muslims.

Police arrested more than 160 people, including Robinson, at their last major demonstration in east London in September when 3,000 officers were deployed to try to maintain order. The EDL achieved greatest notoriety when far-right Norwegian extremist Anders Behring Breivik repeatedly referred to it in a rambling online manifesto he released before killing 76 people. Robinson always distanced himself from any connection with Breivik who he described as a “nutter”.

Quilliam said it hoped to help Robinson channel his energy into fighting all extremism. “We have been able to show that Britain stands together against extremism regardless of political views and hope to continue supporting Tommy and Kevin in their journey,” said Maajid Nawaz, Quilliam’s chairman.

Robinson did not answer his phone yesterday but on his Twitter website he posted a link to the Quilliam statement and commented “hope people listen to my reasons”.