The leader of Newcastle Council has accused anti-Israel activists of “an assault on our Democracy” after councillors were “intimidated” and left “in tears” during a vote on adopting the International Holocaust Remembrance Alliance definition of antisemitism.

Councillors were forced to vacate the council chamber on Wednesday after members of the revolutionary Communist Fight Racism Fight Imperialism group began waving Palestinian flags, chanting and shouting abuse from the public gallery when the motion on the IHRA definition come up. 

One member of the group broke into the council chamber itself and had to be removed by security, while another member of the security team was allegedly assaulted by demonstrators.

Nick Forbes, leader of the Labour-run council, told local paper the Chronicle Live that he hoped “the police throw the book at these clowns. They don't do anything to represent people, they don't do anything to further the cause of the Palestinians.

"We are used to heated debate, but the protest we saw in the gallery tonight, the alleged assault of security staff, the shouting of abuse at councillors, the ranting, and the jumping into the council chamber goes beyond what I think anybody would accept as normal political debate.

"Many of the councillors tonight felt intimidated, several were in tears during the interval we had and were frightened to come back into the council chamber.

"That is, in effect, an assault on our democracy.”

The incident was a day after Labour's National Executive Committee finally adopted the IHRA definition of antisemitism, including all its examples that set out how criticising Israel can be antisemitic.

Before the meeting, the anti-Israel group had presented a petition to the council asking them not to pass the motion.

In the description of its protest on Facebook, Fight Racism Fight Imperialism claimed that the IHRA definition “has nothing to do with anti-racism and everything to do with defending the colonisation of Palestine.

“Among its catechisms is the assertion that those who ‘[claim] the existence of the Israeli state is a racist endeavour’ – which it is – ‘[deny] the Jewish people their right to self-determination’. This is a base attack on solidarity with the Palestinian people.”

After the councillors returned to the chamber in the wake of the protest, the IHRA definition was adopted unanimously by the council, with Mr Forbes agreeing to drop a previously proposed amendment.

He subsequently tweeted he was “proud" the council unanimously agreed to adopt the IHRA definition "despite disruptive anarchists in the gallery howling abuse and attempting to occupy the chamber".

"They do nothing to further the Palestinian cause by such disgraceful behaviour,” he added.

Liberal Democrat councillor Nick Cott, who had proposed the motion, thanked Mr Forbes “for having the political courage to make a stand and second the motion I proposed.

“The people of Newcastle will see we are united in taking a stand against antisemitism.”

Daniel Greenhough, another Labour councillor, tweeted: “Freedom of speech was hard fought for but comes with responsibilities. It is not the freedom to intimidate or bully.

“The actions of individuals last night, including against security staff, are disgraceful. We cannot ever allow them to restrict the democratic process.”