Michael Adebolajo, who is accused of murdering Fusilier Lee Rigby in Woolwich, has begun giving evidence at the Old Bailey.
Adebolajo did not deny killing Fusilier Rigby, but denied murder, saying he was, "a soldier of Allah."
ITV News UK Editor Lucy Manning's report contains details of the killing that some viewers may find distressing:
When asked what his defence to the charge of murder is, Michael Adebolajo said:
I'm a soldier. I'm a soldier of Allah and I understand that some people might not recognise this because we do not wear fatigues and we do not go to the Brecon Beacons and train and this sort of thing. But we are still soldiers in the sight of Allah as a mujahid. This is all that matters, if Allah considers me a soldier, then I am a soldier.
Adebolajo went on to say that does not regret what happened to Fusilier Rigby:
I will never regret obeying the command of Allah. That is all I can say. I'm a mujahid, I'm a soldier, I'm doing what Allah commands me to do. I can't do anything else.
Asked who al Qaida were by his counsel, David Gottlieb, Adebolajo replied: "Al Qaida, I consider to be Mujahideen. I love them, they're my brothers. I have never met them. I consider them my brothers in Islam."
Michael Adebolajo was surrounded by five security guards as he appeared at the Old Bailey.
He and Michael Adebowale, 22, are accused of murdering Fusilier Rigby by running him down with a car and then hacking him to death with a meat cleaver and knives near Woolwich Barracks in south east London on 22nd May.
The soldier's relatives sat feet away as Adebolajo, a married father-of-six, spoke to the court.
He said that, growing up in Romford, the "vast majority" of his friends were white British, and one, Kirk Redpath, joined the Army and was later killed in Iraq.
Adebolajo said: "I hold Tony Blair responsible for his death."
In cross-examination, prosecutor Richard Whittam QC asked defendant Michael Adebolajo: "You and your co-defendant, acting together, killed Lee Rigby, didn't you?"
He replied: "Yes."
The barrister asked: "That's because together you had agreed to kill someone. Do you agree?"
Again, he replied: "Yes."
Adebolajo went on: "We planned a military attack which obviously involved, sadly - it's not something enjoyable, something fantastic - the death of a soldier. It's a military attack."
Just as a general plans attacks knowing full well that when he plans this attack people will die, this is what happens in war, so when we target a soldier this is a similar thing. It's not a casual joke. It's a military operation. This is how we see it.
As well as murder, Adebolajo and Adebowale are both accused of attempted murder of a police officer and conspiracy to murder a police officer, which they deny.
The trial was adjourned until tomorrow.