The UK must sanction the Israeli government and consider suspending it from the United Nations to meet its “fundamental international legal obligations”, more than 800 lawyers, academics and retired senior judges have said.

A letter this week to Prime Minister Keir Starmer, whose signatories include former Supreme Court justices Lord Sumption and Lord Wilson, says there is mounting evidence that genocide is being perpetrated or is at serious risk of occurring in Gaza.

“Your government must act now, before it is too late,” it read, referring to the ongoing abuses by Israel in the besieged territory.

The legal experts, who also include former Court of Appeal judges Sir Stephen Sedley, Sir Anthony Hooper and Sir Alan Moses, urge Starmer to sanction Israeli ministers or senior military officials who they say have incited genocide or supported illegal settlements.

They accuse Israel of “an unparalleled assault on the United Nations” through its banning of Unrwa, the UN agency for Palestinian refugees, and its “attacks on UN premises, property and personnel”.

The signatories say Britain must consider initiating proceedings in the UN Security Council for the suspension of a member state.

Last week, Britain announced it was summoning the Israeli ambassador in London and suspending its free trade agreement talks with Israel in response to its expanded military operations in Gaza.

The government further introduced fresh sanctions on settler leaders and organisations.

But this week the UK’s trade envoy to Israel, Ian Austin, is in Israel to “promote trade”. 

On Monday Austin was in Haifa, where he visited the customs scanning centre, Haifa Bayport and the Haifa-Nazareth Light Rail project.