The schoolboy, who cannot be named, had allegedly previously planned an attack at the Isle of Wight music festival using a pickup truck and knife, but dropped the plan.

He discussed the new plan in chats on a social media forum for video gamers called Discord after setting up an account using an encrypted Proton email address.

Using the name TawidOverKufr - God over disbelief - he joined a group called Caliphate Revivalists, a reference to the area once controlled by Islamic State.

"It was clear from the first message [the schoolboy] posted that he must already know other members in the group," Serena Gates, prosecuting, told Kingston Crown Court.

On 4 July 2022, the boy messaged: "I'm Inshallah [God willing] going to launch an operation today. Please make dua [pray] for me brothers."

A user called 'Abu Aaqib al Albani' asked: "What operation?"

The boy replied: "Destroying kufr [disbelief] in the lands of the kufr is all I'm gonna say although the kufaar [disbelievers] hate it."

Abu Aaqib al Albani asked: "For real? Are you doing something irl [in real life]?"

The youth told him: "I'm generally determined. I have a location which will probably have knives to rob."

Al Albani replied: "I'm gonna do dua [pray] for you."

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The youth went on: "There's a kaafir [non-believer] I know who said something about Muhammad saw [peace be upon him] which would enrage anyone with iman [faith]."

Al Albani asked: "U gonna kill him?" and added: "Film it."

The boy told him: "Inshallah [God willing]. Let me say why, so we understand. This kaafir said his girlfriend makes pictures of Prophet saw out of pork. These evil imbeciles deserve nothing more but to be slaughtered and if what mentioned does not enrage [you], then iman is not fully there."

Ms Gates told the jury the conversation was a reference to an "ill-advised joke" made by the boy's tutor at his educational unit about a fictitious girlfriend called Jaqueline working in a meat processing plant, packing pork chops in the shape of the prophet.

The boy, now aged 16 and from the Isle of Wight, denies planning a terrorist attack and the case continues.