BRITAIN’S youngest female terror plotter has today been jailed for life over a plot to bomb London after a judge rejected her claims she has been deradicalised.

Safaa Boular, 18, was branded the “Mad Hatter” after she used coded language with an Alice in Wonderland tea party theme to discuss the murderous scheme.

She even went on a “reconnaissance journey” around major landmarks in Westminster — taking a chilling selfie outside M16 headquarters.

Safaa has now been jailed for life with a minimum of 13 years at the Old Bailey Criminal Court in London after being found guilty of preparing acts of terrorism abroad and in the UK.

She is the youngest female to be charged with planning an IS attack in the UK.

Her lawyers told the court the teenager had been “groomed” into Islamist ideas and is now “no longer a Muslim”.

But Judge Mark Dennis QC rejected that, saying: “In my view there’s insufficient evidence to say at this stage this defendant is a truly transformed individual. Her views were deeply entrenched.

“However much she may have been influenced and drawn into extremism, it appeared she knew what she was doing and acted with open eyes.”

Safaa first began planning a grenade and gun attack on the British Museum when she was thwarted from joining her ISIS husband in Syria.

She then passed the baton to her sister Rizlaine, 22, after she was arrested and remanded in custody for trying to travel to the war zone.

Her fellow plotters admitted their roles before the trial and were sentenced in June.

Rizlaine received life imprisonment with a minimum of 16 years and their mother, Mina Dich, 44, was jailed for an extended sentence of 11 years and nine months — six years and nine months in prison and five years on licence.

Judge Dennis said: “It would appear that by 2012, 2013, a new theme had emerged in the family, namely Mina Dich’s increasing move towards a conservative and ultimately more extreme version of the Islamic faith.

“This affected not only her mindset and approach to daily life but also that of her daughters.”

The women were snared in a “proactive” investigation involving surveillance by counter-terrorism police and MI5 agents posing online as IS operatives.

Counter-terrorism chief Dean Haydon, of Scotland Yard, said the case demonstrated a worrying rise in youngsters being arrested for terrorism.

The court heard how Safaa was just 16 when she was wooed online by Coventry-born IS fighter Naweed Hussain, 32.

The couple got married in an online ceremony and talked of donning his-and-hers suicide belts to achieve martyrdom together.

Police uncovered Safaa’s plans to join him following an airport stop in August 2016 and confiscated her passport.

While on bail, Safaa turned her attention to an attack on the British Museum, encouraged by Hussain in “lovey-dovey” messages.

Burka-wearing Safaa also scoped out the MI6 headquarters near her home, and took a selfie in front of the building, the court heard.

Hussain was lured into revealing his murderous intentions to British secret service agents posing as IS supporters online before he was killed in a drone strike.

When an agent pretending to be his commander informed Safaa of his death on April 4 last year, she was wracked by grief and resolved to join him.

She revealed to the undercover officer that Hussain had talked about attacking the British Museum with a “tokarev” Russian-made pistol and “pineapples” — code for grenades.

On being remanded in custody over her attempt to travel to Syria, Safaa persuaded her fellow IS supporter sister to take over.

In coded telephone calls involving their mother Mina, the sisters discussed a traditional English tea party with an Alice in Wonderland theme.

Rizlaine said she knew “a few recipes for some amazing cakes” for a “proper like English tea party kind of thing”.

Safaa suggested an “Alice in Wonderland theme” telling her sister: “You can be the Mad Hatter cause your hair’s crazy”.

Mother-of-four Mina responded: “That will be fun”.

Rizlaine then scoped around the Palace of Westminster and bought knives and a rucksack from Sainsbury’s.

She was accompanied by her mother, unaware that they were under surveillance by counter-terrorism police.

Rizlaine even practised a knife attack at her home in Willesden, north west London.

She was shot when armed police moved in to arrest the gang but went on to make a full recovery.

Safaa, who viewed gory beheadings and chatted about killing US President Barack Obama, told jurors: “Nothing online is real.”

In the year since she had been in custody, she said she had changed and now opts to wear Western clothes rather than a burka.

Rizlaine and Mina, from Vauxhall, south London, pleaded guilty to preparing acts of terrorism and Barghouthi admitted failing to alert authorities.