LONDON (Reuters) - The head of a banned British radical Islamist group who knew one of the men who hacked a soldier to death on London's streets said on Thursday that British foreign policy was to blame for the attack.

Mr Anjem Choudary said Michael Adebolajo - filmed with his hands covered with blood, carrying a meat cleaver and knife after attacking an off-duty soldier in broad daylight - had attended lectures run by Al-Muhajiroun, Mr Choudary's organisation, which was banned under anti-terrorism laws in 2010.

"He used to attend a few demonstrations and activities that we used to have in the past," Mr Choudary told Reuters, adding he had not seen him for about two years.

"When I knew him he was a very pleasant man, he was peaceful, unassuming and I don't think there's any reason to think he would do anything violent."

Mr Choudary's organisation gained notoriety for staging events to commemorate the Sept 11, 2001 attacks on the United States with leaflets that referred to the hijackers as "the Magnificent 19".

Its Syrian-born founder Omar Bakri was banished from Britain in 2005.

Mr Choudary has always maintained that Al-Muhajiroun forbids its followers in Britain from carrying out attacks there under a "covenant of security" demanded of Muslims in non-Muslim lands.

"I would not consider him to be a member of the organisation I don't think he was intellectually affiliated, he was a contact. He used to attend some stuff," Mr Choudary said of Adebolajo. He said he did not recognise the other suspect, but had not seen clear images of him.

"If you are a practising Muslim male and you want to do something then you'll probably come across us at one time or another so I don't think you should be surprised that he's been attending some of our activities."

Sources familiar with Britain's investigation of the two suspects say both were British men of Nigerian heritage, and both were on the radar of the authorities before the attack.

Acquaintances have identified Adebolajo, who was filmed explaining the motives for the attack, as a convert who grew up as a Christian.

He attended Marshall's Park school in Romford, an overwhelmingly white suburb on London's north-east outskirts.

"I'm not in the business of condemnation or condoning," Mr Choudary said of the attack. "I think if anyone needs to be condemned it is the British government and their foreign policy. It's so clear that that is the cause."

He added: "I think we're all shocked by it. But he said it all in that clip... He blamed (Prime Minister David) Cameron and he blamed the army and the authorities, and he said that the British public should do something about it because they're not doing anything in their names.

"From the statements that he's made himself, it's clear that that was being targeted. The cause is clear - it's the British foreign policy."

Mr Choudary's organisation has been known for staging protests at funerals of British troops and for burning the paper poppies that Britons wear annually in November to commemorate their war dead.

It called its Remembrance Day protest "Hell for Heroes", a variation of the name of the veterans' charity "Help for Heroes", whose T-shirt was worn by the soldier victim.

One of Mr Choudary's followers Richard Dart, converted to Islam by him, pleaded guilty to terrorism charges in March.

The authorities said Dart had discussed attacking Royal Wootton Basset, a town that holds ceremonies for British troops killed abroad whose bodies are repatriated to a nearby airfield.

Mr Choudary said banning organisations like Al-Muhajiroun increased the chance of attacks taking place in Britain.

"I believe Al-Muhajiroun is very beneficial for people to express their anger. When you start to ban organisations from merely thought crimes and because you don't agree with what they say about foreign policy, then I don't think you should be surprised that people manifest their anger in different ways.

"They are doing these kind of lone wolf, or DIY (do-it-yourself) type operations.

"I'm not going to stop talking about the foreign policy. I'm not going to say Muslims in Muslim countries who are being bombed don't have a right to defend themselves. If that's being radical, then yeah I'm a radical. But in terms of targeting people, in terms of carrying out these operations, we are very clear on our stance in the covenant of security."