Video report by ITV News Security Editor Rohit Kachroo
A neo-Nazi movement is set to become the first extreme right-wing group in the UK to be banned as a terrorist organisation.
Being a member of, or inciting support for National Action, will constitute a criminal offence from Friday.
An order was laid in Parliament on Monday to proscribe the group under the Terrorism Act 2000 and will come into effect by the end of the working week.
National Action was branded a "racist, anti-Semitic and homophobic" organisation by Home Secretary Amber Rudd.
Announcing the move, Ms Rudd said: "As Home Secretary, I am clear that the safety and security of our families, communities and country comes first.
"So today I am taking action to proscribe the neo-Nazi group National Action".
She added: "National Action is a racist, anti-Semitic and homophobic organisation which stirs up hatred, glorifies violence and promotes a vile ideology, and I will not stand for it.
"It has absolutely no place in a Britain that works for everyone".
National Action says it is a radical group not a terrorist group.
The phrase "Death to traitors, freedom for Britain!" - which was said by MP Jo Cox's killer Thomas Mair in court - appears alongside the listing for National Action's website on Google.
Its website said it presents itself as a "scene for young nationalists to network, engage socially, and be creative".
It added: "We carry out demonstrations, publicity stunts, and other activities in order to grow and spread our message, that of National Socialism."
The Home Secretary decided to ban National Action before Mair's trial.
But in the wake of his conviction, warnings emerged that there are signs that the terror threat from the extreme right could be growing.
Gideon Falter, chairman of the Campaign Against Antisemitism, said: "This decision by the Home Secretary is something we have long called for and sends a strong message that the far-right is in the Government's sights and will not be permitted to continue its incitement and violence."