But yesterday three of the July 7 bombers were seen in sickening home video footage laughing and joking together along with one of their alleged conspirators, as the group's ringleader Mohammed Sidique Khan introduced his seven-month old child to them.

Waheed Ali is one of three men accused of conspiring with the four suicide bombers in the run up to the terrorist atrocity in 2005.

Yesterday, a jury was shown video footage of Ali and London bombers Shezhad Tanweer and Hasib Hussain talking to Khan as he paraded his seven-month-old daughter Maryam before them.

The trial at Kingston Crown Court was shown two tapes which were filmed a month apart in 2004, before Khan and Tanweer flew to Pakistan seeking martyrdom. Their plans then changed for some reason, and they returned home with the intention of targeting the UK.

Khan taped himself saying an emotional farewell to his daughter as he cradled her on his lap, during which he calls her "the happiest thing in my life".

The jury was also shown footage of the group's ringleader introducing Tanweer, Hussain and Ali to his daughter as her "uncles".

Ali is then seen cradling the seven-month-old and putting his baseball cap on her head. The footage also shows the 24-year-old flexing his muscles and kissing his biceps in front of the camera.

Ali, 24, who is originally from Beeston but later moved to London, Mohammed Shakil, 31, and Sadeer Saleem, 27, both from Beeston, are said to have helped the July 7 bombers by scouting for possible targets in London some seven months before the attacks on the capital.

In the film, made on October 26, 2004, Khan shows his daughter to Tanweer, Ali and Hussain, holds her in his arms, and says: "You're a cute little baby." He then asks the men for a "few words of wisdom", to which one replies: "Kill everyone there is."

The jury were also shown a second home video made a month later in which Khan says goodbye to his daughter and tells her to look after her mother. He tells her he is "doing what he is doing for Islam".

The recording has chilling echoes of a video released on Arab TV just two months after the bombings in which Khan said he was a "soldier" and warned the British people "we are at war".

The home video featuring Khan's little girl was shown by the prosecution yesterday, who allege that Ali, Saleem and Shakil conspired with Khan, Tanweer, Hussain and Jermaine Lindsay to cause explosions between November 2004 and July 8, 2005. All three men deny the charges.

The court has previously heard that traces of DNA from Ali and Saleem were found at a "bomb factory" in Leeds.