More than a thousand local councillors have signed a pledge of solidarity with the Palestinian people.
With so many Labour-run councils already in jeopardy in the forthcoming local elections, campaigners believe this could be a deciding issue in key areas.
But the Israeli embassy says the pledge is a "disgraceful effort at intimidation".
In total, 1,028 councillors have now signed up to "uphold the inalienable rights of the Palestinian people" and ensure their council is not complicit in what they claim are "Israel's violations of international law", such as divesting from pension funds invested in arms companies.
Among the signatories is Hackney Green Councillor Zoe Garbett.
"I think that this is really important to uphold the rights of the Palestinian people and to make sure that we can make ethical investments," she told Sky News, adding that this was an issue that residents had raised with the council.
"They want to see their council representing them on a national level," she said.
"We know that most people really want to see an end to the genocide in Gaza, and an end to wars and conflicts all across the world, and they want to see their local representatives standing up for them."
Israel denies the accusations of genocide in Gaza.
Most signatories from Green and Labour parties
So far, 345 of the councillors who've signed the Palestine Pledge are from the Greens, followed by 338 from Labour, 104 Lib Dems, 38 members of the SNP, 17 from Plaid Cymru, 12 from Your Party, three Conservatives and many more independents.
Labour has long been divided on the issue of Gaza.
The prime minister's initial reluctance to call for a ceasefire after the October 7 attacks led to a drop in support among Muslim communities at the last election. Four Labour MPs lost their seats to pro-Palestinian candidates in July 2024, and the party is now under increasing pressure from other parties on the left.
Read more: What's happening with this year's local elections?
The pledge provides a rough indication of where it could be a factor in the local elections.
In Labour-dominated Islington, 59% of councillors pledged, mostly from Labour. In Tower Hamlets, 49% have signed up, nearly all from the controlling group on the council, Aspire, and none from the Labour block of 16 councillors.
In Sheffield, where no party currently has overall control, 24% have signed up - including 13 Greens and seven Labour councillors.
But in Labour-controlled Bradford, 29% have signed up - the majority are Greens and independents. In Hackney - where there have been big debates over the issue of divestment - 16% have pledged, with just three of them from Labour.
Pledges from Labour left
While the prime minister recognised Palestinian statehood in September, many on the Labour left would like to see him do more.
"I think that so many Labour councillors have been so keen to sign the Palestine pledge as councillors because it puts on record that support for Palestine and distinguishes them from the position taken by the leader of the Labour Party," Richard Burgon, Labour MP for Leeds East, said.
The pledge was launched by the Palestine Solidarity Campaign - the group behind many of the protest marches in support of the Palestinian cause - and supported by four other organisations, the Palestinian Youth Movement Britain, the Palestinian Forum in Britain, The Muslim Vote and the British Palestinian Committee.
'Dangerous road to go down'
Former MP Lord Steve McCabe, from Labour Friends of Israel, is concerned about the potential impact of the pledge, saying the campaign was "trying to interfere in local elections" and "encourage councils to develop their own foreign policies".
"I think it's a dangerous road to go down. I think undoubtedly it could create tensions in some communities," he said.
Lord McCabe added that the campaign comes at a time of heightened antisemitism. He said: "Jewish people are alarmed. They're scared to go to their synagogue. Sometimes they're frightened to walk the streets of their own community. How this will do anything to relieve tensions, I can't see."
A spokesperson from the Israeli embassy in London said: "Contrary to what has been portrayed in the campaign, Israel is actively engaged in implementing the 20-point programme established by the Board of Peace.
"It is regrettable to see small-scale political opportunism and grifting carried out on the backs of people in the Middle East.
"The BDS [Boycott, Divestment, Sanctions] campaign is a disgraceful effort at intimidation that echoes some of the darkest chapters of history. Calls for boycott[s] should be rejected."
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Dan Iley-Williamson, political organiser at the Palestine Solidarity Campaign, said local authorities "administer pension funds that invest more than £12bn in companies enabling Israel's crimes, including in arms firms that make the bombs and bullets used to kill Palestinians".
"The mass movement for Palestine - which has brought millions onto Britain's streets - is not going away," he added.
"Vote Palestine will take our demands into the May elections and deliver a message to those seeking office: If you want our votes, stand up for Palestine."
The government says it "formally recognised Palestine in the autumn to protect the viability of a two-state solution and create a path towards lasting peace for the Israeli and Palestinian people".
(c) Sky News 2026: Over 1,000 councillors sign Palestine solidarity pledge amid claims of 'political opportunism'

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