After the initial shock over the Greens branding Zionism as racist, the ensuing fallout from a motion widely seen as antisemitic reverberated across Westminster.
The knock-on effect may have appreciably altered the political map for Britain, as Andy Burnham is rumoured to be considering call an early election next year.
Early on Wednesday morning, Nigel Farage called on the prime minister to explicitly rule out partnerships with Zack Polanki’s party.
Writing exclusively in the JC, Reform UK’s leader said: “Labour’s leadership must now speak plainly and immediately. They must reject any electoral alliance with the Greens.
“They must rule out any coalition whatsoever and make it clear that a party which has chosen antisemitic dogma has no place at the cabinet table.”
It’s true that prior to Wednesday, Burnham had condemned the Greens’ motion.
All well and good: however, he didn’t go so far as to rule out any formal pacts with the Greens, much to the frustration of some Labour figures I’d spoken to.
One former minister reacted to the Reform UK leader’s call for a “red line” against the Greens, saying: “I’m no fan of Nigel Farage, but he’s absolutely correct here,” adding: “It is shocking that the party didn’t explicitly rule out an alliance with the Green Party the moment they passed their racist motion.”
But a few hours later on Wednesday, at Prime Minister’s Questions, Burnham promised action.
In a response to a question from Conservative MP Dame Harriet Baldwin, he described the Greens’ new policy as “antisemitic” and, for the first time, ruled out any “partnership” with the party.
He told MPs: “We will always take the right response when it comes to any partnerships we have with other parties. We cannot support a partnership with a party that holds a position that has recently been adopted.”
On Thursday, the party spelled out the details of what this meant, including when Labour has power sharing agreements with the Green Party in local government.
In essence, the local Greens have to repudiate the national party and explicitly reject the “Zionism is racism” policy within a week, and if they don’t, “any local power sharing agreement will end”.
Labour Party chair Bridget Phillipson expanded: “Where local Labour Parties currently have an arrangement with the Greens in local government, we expect their Green counterparts to make clear that they reject this position and to call on their national leadership to reconsider the policy.
“We have asked local Green groups to respond as a matter of urgency. Where they are unable to provide that assurance, Labour will bring any such local arrangement to an end. This isn’t an issue of party politics; it’s about doing what is right and upholding the values anyone holding public office should share.”
Jewish communal groups including the Board of Deputies and Jewish Leadership Council celebrated the decision, as did Labour MPs.
Sarah Sackman, justice minister and MP for Finchley and Golders Green, told my colleague Jane Prinsley: "I fought against Corbyn-era antisemitism in the Labour Party. I know how dangerous it is to give it any space to fester. As we see an antisemitic motion adopted as Green Party policy, I will be a relentless voice inside government to ensure we fight against it. I am pleased the Prime Minister shares my view that we must hold firm to our principles, and establish a firewall against any partnerships with Greens who believe that Zionism is racism."
The Jewish Labour Movement also referred back to the antisemitism crisis of the Corbyn years as they welcomed Burnham’s position.
A spokesman said: "The Labour Party should never be in coalition with those who are allowing racism and antisemitism to flourish. We know all too well what happens when antisemitism takes over a political party.
“Labour Groups must do the right thing and end power sharing agreements with the Greens if they do not disavow their Party’s decisions.
“We are encouraged by, and support the action taken by the Labour Party. It’s with the memory of what happened to the Labour Party under Jeremy Corbyn that the Labour Party has taken this action."
Needless to say, the Green Party wasn’t too happy with all this, a spokesperson telling me: “For the Labour government to conflate criticism of Israel with antisemitism is disappointing and wrong. Trying to tell local parties what to do and who they can work with is undemocratic. Whilst Labour continue to try to meddle in our internal democracy, arm a genocide and lock up protesting pensioners, we will not take lectures from them.”
Britain’s equalities watchdog – the Equality and Human Rights Commission (EHRC) – is now asking them serious questions about the potential impact of their new policy.
It has written to the Green Party to ask for “more information” to “assess its practical implications and potential impact”, after receiving complaints under the Equality Act about the motion, which has been widely criticised as antisemitic.
This hasn’t just happened in a vacuum and serious voices, including human rights barrister Adam Wagner KC and Lord Mann, the government’s independent adviser on antisemitism, have raised serious concerns about the practical implications of the policy adopted by Zack Polanski’s party.
A likely consequence of the EHRC’s intervention is that the activities of the Green Party will be put under further scrutiny.
And let’s just say, the JC’s politics team hasn’t exactly had to struggle to find unflattering stories about the Greens.
Labour’s move to shun the Greens – following Farage and Kemi Badenoch – also puts pressure on the Lib Dems.
While they’ve condemned the Zionism is racism motion, the national party has refused to issue any edict against partnering with the Greens, insisting this is a matter for local parties.
Whether this line will hold remains to be seen. I suspect that being seen to align with the Greens won’t exactly endear the Lib Dems to potential swing voters in so-called “blue wall” constituencies they hope to win off the Tories at the next election.
For that matter, you don’t need to be a cynic to wonder if Burnham’s pledge would hold good next year, in the event that the result of an early election forced Labour to look to the Green Party for coalition support.
Politics can be a brutal business for any party when it comes to holding on to power.
To get more from opinion, click here to sign up for our free Editor's Picks newsletter.