Lucy Galvin issued a statement saying she and her cabinet were “opposed” to the declaration, which was passed at her party’s conference on Sunday.
However, the reference to her cabinet suggests that not all Greens at City Hall are prepared to support her position.
One Green councillor, Amber Smith, has already indicated that she supports the view that Zionism – the belief in a Jewish homeland which is shared by most British Jews – is racist.
The Board of Deputies of British Jews and the Jewish Leadership Council have described the motion as an “an attack on the Jewish community” and “an antisemitic platform, based on a grossly offensive distortion and erasure of Jewish experience and identity”.
They added: “Zionism is anti-racism, creating a refuge for Jews in their ancient homeland after millennia of persecution outside it.
“Branding most British Jews and Jewish institutions ‘racist’ stokes anti-Jewish hatred after a year in which British Jews have been murdered attending their synagogue, stabbed in the streets, and seen their community buildings firebombed.
“With this motion the Green Party has departed far from international consensus and exposed itself as an extremist party.”
Amid the widespread outrage, Greens across the country have been coming under pressure to give their views on the issue.
Earlier this week, Ms Galvin restated the party’s opposition to antisemitism but stopped short of opposing the motion itself. She has now gone further.
Zack Polanski did not cast a vote on the motion (Image: PA)
She said: “My cabinet and I are opposed to the motion passed at Green Party Conference on Sunday 4 October, and it is not, and will not become, any part of Norwich City Council policy.
“Our focus is, and remains, on bringing communities together, promoting understanding and ensuring Norwich City Council works in the interests of all residents.
“We reject antisemitism in any form and as I meet with faith leaders from across our city, I am reaffirming our commitment to this.
“We are here to serve everyone, regardless of their faith, beliefs or background. Our city is diverse and inclusive – and we are committed to bringing people together and promoting understanding.”
Ms Smith, who represents Bowthorpe on both Norwich City Council and Norfolk County Council, was the first Green elected representative in Norfolk known to have publicly backed the motion.
Amber Smith, pictured here with leader Zack Polanski, is the only Norfolk Green to have supported the Zionism motion (Image: Bowthorpe Green Party / Facebook)
On the Bowthorpe Green Party’s social media accounts, which she runs, she has defended the motion in two posts.
The first was posted on Sunday after the vote was passed and the second was uploaded after this newspaper approached her about her support for the vote.
Her second defence on Wednesday saw her share a post which accused “the British state and the media which serves it” of “coming down on the Palestinians behind the Greens [sic] historic call for liberation”.
Carli Harper, leader of the Labour group at City Hall, welcomed Ms Galvin’s statement but warned that the split with one of her own councillors could not be brushed aside.
She said: “I welcome this clear statement from the Leader of Norwich City Council and her cabinet, and their unequivocal commitment to rejecting antisemitism and ensuring that the motion passed at Green Party Conference will have no place in council policy.
Carli Harper, the leader of the Labour group at City Hall (Image: Newsquest)
“It is important that Norwich’s Jewish community hears that reassurance, particularly at a time when many are feeling increasingly anxious and vulnerable.
“However, the contradiction between her statement and the public position taken by one of her own councillors cannot simply be ignored.”
The motion, passed by 1,022 votes to 813, defines Zionism as an ideology supporting “an ethnonationalist Jewish state”.
Four of the party’s five MPs publicly rejected it, including Adrian Ramsay, the Waveney Valley MP and former co-leader, who said he was “deeply saddened” by the result.
Adrian Ramsay, the Waveney Valley MP and former co-leader, said he was “deeply saddened” by the result of the vote. (Image: Roger Harris/Parliament)
He has denied he is planning to leave the party after the vote, but others have already done so.
Phil Davies, the Greens’ deputy leader in Wales, resigned on Tuesday.
In Suffolk, Daniel Potter, a Babergh District councillor, defected to the Conservatives. He told this newspaper that other local representatives within the party are also considering their future.
Ms Smith has been approached for comment.