A man accused of killing an off-duty British soldier in a frenzied knife attack on a London street defended his actions in court Monday, saying he carried out the attack because he is a soldier fighting in the service of God.

Michael Adebolajo, 28, said that he attacked soldier Lee Rigby because he wanted to protest Britain's invasion of Muslim lands. He claimed to be one of many fighters engaged in a war between Islam and Western countries.

"I'm a soldier ... I couldn't do anything else," he said when asked whether he had any regrets.

Adebolajo spoke calmly and clearly as he was cross-examined at London's Central Criminal Court on Monday, telling jurors that while he had never met anyone from al-Qaida, he was full of admiration for the terrorist group.

"I love them. I consider them brothers in Islam," he said.

Adebolajo and fellow defendant Michael Adebowale, 22, are accused of murder in connection with Rigby's death, a brutal slaying that shocked the country. Both deny the charge, and Monday's hearing was the jury's first chance to hear directly from one of the defendants about what led to the attack.

Adebolajo laid out his life story, saying his parents were Christian and he used to read from the Bible, but he became frustrated and converted to Islam during his time in university. He said he had tried to travel to Somalia so that he could live under Sharia law, but was detained by Kenyan troops before he could get there.

Turning to the attack, he said that he tried to make sure that Rigby was a soldier before he killed him, saying he hoped the death could "indirectly save the lives of many."

"I was keen that the reason for the death of this man is not misunderstood. I wanted people to understand ... It only happened for one reason only, and that is foreign policy," he said.

Adebolajo said he rushed at the police who arrived at the scene minutes after the killing because his religion forbade him to run away from the enemy.