One of the alleged 21 July bombers has admitted in court taking a "device" onto a London bus but said he did not intend to cause an explosion.
Mr Ibrahim admitted he was the man pictured on the No 26 bus
Giving evidence at Woolwich Crown Court Muktar Said Ibrahim, 29, said he had the device with him to protest against the plight of Muslims everywhere.
His defence lawyer has already told the court he tested the devices beforehand to make sure they only went "pop".
Six defendants deny conspiracy to murder and to cause explosions.
Mr Ibrahim is the first of the six defendants - accused of being part of an extremist Muslim plot to explode bombs on London's transport network - to appear in the witness box.
Dressed in trousers, a pale grey checked shirt and tie with a goatee and moustache he swore on the Koran before answering questions from his defence counsel George Carter-Stephenson.
He immediately conceded he was the man on the No 26 bus who was caught on CCTV apparently detonating a rucksack.
Mr Carter-Stephenson said: "Did you have - to describe it neutrally - a device with you?"
Mr Ibrahim replied: "Yes."
Mr Carter-Stephenson asked: "Did you intend or hope that that device would explode?"
The defendant said: "No."
Mr Carter-Stephenson asked: "Was the device an improvised explosive device, in other words, was it to your knowledge capable of detonation?"
Mr Ibrahim replied: "No."
Counsel asked: "In a short sentence, can you help this jury as to why you had that device with you on July 21?"
He replied: "To protest against the plight of Muslims everywhere, especially in Iraq."
Mr Ibrahim, of Stoke Newington, north London, told the court he was born in Eritrea and moved to the UK with his family in 1990 to escape the war with Ethiopia.
He said his family settled in north west London and he had lived in the UK ever since.
He left school in 1994 with two GCSEs and went on to Harrow Weald College to study leisure and tourism, a course he did not finish.
He met his co-accused Yassin Omar in 2000, he said.
He travelled to Sudan in January 2003, where he stayed for two months visiting relatives, the court heard.
Asked if he engaged in anything in Sudan that could be described as jihadic or military training, he answered "no".
He denied telling anyone he had learned to fire or had ever used a rocket-propelled grenade.
Manfo Kwaku Asiedu, Hussein Osman, Yassin Omar, Ramzi Mohammed and Adel Yahya are also accused of plotting the failed attacks as part of an extremist Muslim plot.