A British teenager who plotted a terrorist “massacre” at Australia’s Anzac Day parade aged just 14 has been given a life sentence.

The boy, who cannot be named for legal reasons, was sentenced at Manchester Crown Court today after pleading guilty to inciting terrorism overseas.

He will serve at least five years of his sentence, which is automatically reduced for minors.

Mr Justice Saunders said the defendant's life term meant he would not be released until he is considered not to be dangerous.

Dcreenshot image found on defendant's phone that police said showed him plotting the Anzac Day attack. (Greater Manchester Police)

"Thanks to the intervention of the police in this country and in Australia, that attack and the deaths which were intended to follow never happened,” he continued.

"Had the authorities not intervened, (the defendant) would have continued to play his part hoping and intending that the outcome would be the deaths of a number of people.

"He would have been pleased if that had happened. He would have welcomed the notoriety that he would have achieved."

The judge said that the fact a 14-year-old could become so radicalised that he could wish for innocent people to be murdered was “chilling”.

He ruled that reporting restrictions that ban the identification of the Muslim defendant should remain, preventing him from being named.

The bespectacled teenager, wearing grey trousers, a grey shirt and patterned tie, hugged his parents and relatives before he was led from the courtroom.

A wallpaper on the defendant's phone, discovered hidden under his mattress by police, showing Isis propaganda. (Greater Manchester Police)

Dubbed “Britain’s youngest terrorist”, the boy orchestrated a plan to run over and behead police officers in Melbourne that was discovered just days before it could be carried it out.

The court heard that the defendant, now 15, communicated with an Australian jihadist from his bedroom at his parents’ house in Blackburn.

Prosecutors said he became “organiser and adviser” to 18-year-old Sevdet Besim, with the pair exchanging more than 3,000 after becoming radicalised by Isis’ gory online propaganda.

Besim was arrested in possession of a knife a week before the annual war remembrance event on 25 April this year.

Scrutiny is expected to turn on to anti-radicalisation agencies who had the British defendant referred to them twice as he espoused extremist views.

ANZAC Day in pictures Show all 12 1 /12 ANZAC Day in pictures ANZAC Day in pictures Anzac-Day2-ap.jpg Australian visitors walk around during a ceremony at Tyne Cot Cemetery in Belgium - the world's largest British and Commonwealth war cemetery - to commemorate the Australian and New Zealand soldiers during the First World War AP ANZAC Day in pictures Anzac-Day7-gt.jpg A war veteran makes his way down Bathurst Street during the ANZAC Day parade in Sydney Getty Images ANZAC Day in pictures Anzac-Day18-gt.jpg A woman carries photos of a relative during the ANZAC Day parade in Sydney Getty Images ANZAC Day in pictures Anzac-Day1-gt.jpg Hundreds of Australians listen during the sunrise memorial service in Hellfire Pass in remembrance of all those who lost their lives on Anzac Day Getty Images ANZAC Day in pictures Anzac-Day4-afp.jpg Australians and New Zealanders attend a ceremony marking the 98th anniversary of Anzac Day at Anzac Cove AFP/Getty Images ANZAC Day in pictures Anzac-Day3-gt.jpg Former Australian POW Gordon Jamieson, 92, listens to speeches during the Wreath Laying Ceremony at the Kanchanaburi War Cemetery in Thailand Getty Images ANZAC Day in pictures Anzac-Day5-afp.jpg Australians and New Zealanders attend a ceremony marking the 98th anniversary of Anzac Day at Anzac Cove, in western Canakkale AFP/Getty Images ANZAC Day in pictures Anzac-Day9-gt.jpg Servicemen make their way down Bathurst Street during the ANZAC Day parade in Sydney Getty Images ANZAC Day in pictures Anzac-Day8-gt.jpg Crowds line George Street during the ANZAC Day parade in Sydney Getty Images ANZAC Day in pictures Anzac-Day6-afp.jpg The moon sets over the Australian War Memorial in the northern French city of Villers-Bretonneux AFP/Getty Images ANZAC Day in pictures Anzac-Day17-ap.jpg Children attend a dawn service ceremony at Buttes New British Cemetery in Belgium to commemorate the Australian and New Zealand soldiers who fought during World War I AP ANZAC Day in pictures Anzac-Day16-gt.jpg Archive footage is projected onto the walls of the Auckland Museum prior to ANZAC Day on 23 April Getty Images

The boy allegedly praised Osama bin Laden, as well as the two al-Qaeda-inspired men who carried out the Charlie Hebdo massacre, who he called “his heroes”.

Just two weeks after creating a Twitter account and posting extremist messages, he had 24,000 followers and “quickly became a celebrity” among the jihadi community, defence lawyer James Pickup QC told the court, saying the new-found popularity “filled a void” in his life.

The defence argued that the teenager had felt isolated because of a medical condition and problems at school and home after his parents separated.