Zack Polanski has been accused of discriminating against Israelis after he backed a campaign calling for a list of Britons who have served in the Israel Defence Forces (IDF) since October 7.
The Green Party leader signed a petition demanding that the UK government "implement a disclosure requirement regarding service in the Israeli military" and introduce a "secondary screening" process for travellers arriving in Britain from Tel Aviv.
The letter also called for "investigations and prosecutions at national or international levels" of those who have served in the IDF.
The Board of Deputies slammed the petition as an “attempt to demonise Israelis and promote an atmosphere of intimidation against British Jews,” which it branded as a “wholly unacceptable form of discrimination”.
Launching the campaign, activist group the International Centre of Justice for Palestinians (ICJP) and news website Declassified UK said it aimed to signal "the end of impunity for British nationals who fought for Israel in Gaza".
It follows a report by Declassified on Freedom of Information requests to the IDF, which suggested that some 2,000 UK citizens have served in the Israeli military since October 7.
The letter warned that former IDF personnel "may now be living alongside us" and stated: "Nobody wants to live next to a potential war criminal."
"Individuals who have returned from fighting in Gaza may now be living alongside us and working in public institutions such as hospitals, the police, and schools,” the letter read.
"Nobody wants to live next to a potential war criminal – not least members of the Palestinian community in the UK who have family or friends who have been subjected to war crimes."
Other signatories include Diane Abbott, the mother of the House and independent MP; former Labour leader Jeremy Corbyn; independent MPs Shockat Adam, Ayoub Khan, Iqbal Mohamed and Zarah Sultana; and Labour MPs Brian Leishman and John McDonnell.
Among the other signatories are Bindmans lawyer Tayab Ali, rapper Lowkey and former Greek Finance Minister Yanis Varoufakis.
The letter cites a United Nations Commission of Inquiry which, it says, found that Israel committed "genocide" and "the crime against humanity of extermination" in Gaza.
"The UK government must immediately implement the above measures in order to ensure sufficient scrutiny of IDF soldiers returning to the UK, in the interests of international and domestic law, transparency, and public safety," the letter continues.
There have been repeated unsuccessful attempts in recent years to bring legal cases against British-Israeli soldiers.
In April, a judge dismissed a case brought by the ICJP against a reservist who returned to Israel following October 7 as "vexatious" and "politically motivated".
Last month, the Metropolitan Police’s War Crimes Unit announced that it had closed an investigation into ten Britons who had been accused of war crimes and crimes against humanity while serving in the IDF in Gaza.
Russell Langer, director of public affairs at the Jewish Leadership Council, said it was “disturbing to see calls for the monitoring of dual British-Israeli citizens.
“Demonisation of Israelis is not a criticism of a foreign government but the targeting of a group of people for their nationality. Such hatred risks making British Jews, many of whom have close family and social connections to Israel, a target for hostility and violence,” Langer said.
A spokesperson for the Board of Deputies said the petition was “an example of what the government’s independent reviewer of terrorism legislation, Jonathan Hall KC, has described as the ignoring of conventions against the promotion of collective hatred against a nationality in the case of Israelis.
A spokesperson for Polanski said: "The IDF has been credibly accused of horrific war crimes in Gaza by bodies including the UN Human Rights Council, Human Rights Watch and Amnesty International, and the UK government should be taking robust action against any British citizen complicit in these crimes."
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