The UK government will, for the first time, legally redefine a non-violent protest group, Palestine Action, as a "terrorist organization" after a last-minute legal challenge to suspend the group's ban under anti-terrorism laws failed at a high court.

As of Saturday, membership in, or showing support for, Palestine Action will become a criminal offense, TRT Global reported.

The group, known for its direct-action campaigns targeting Israeli weapons factories and their UK supply chains, is the first protest organization to be banned under the UK Terrorism Act.

Lawyers acting on behalf of Huda Ammori, the group's co-founder, had sought to prevent the ban from taking effect, arguing for interim relief ahead of a scheduled judicial review.

However, following a hearing at the high court on Friday, Justice Martin Chamberlain declined to grant the application. He said that an assessment on whether to ban the group had been made as early as March.

"This is the first time in our history that a direct action civil disobedience group, which does not advocate for violence, has been sought to be proscribed as terrorists," Raza Husain KC, representing Ammori, told the court.

He said his client has been "inspired" by a long tradition of nonviolent protest in the UK, "from the suffragettes to anti-apartheid activists to Iraq War activists."

Four Palestine Action activists were remanded in custody on Thursday after appearing in court.