Legal professionals issued an open letter Monday, urging the UK government to take “concrete action” against Israel and meet its obligations under international law to prevent war crimes and other violations against the Palestinian people.

The letter, addressed to the UK primemMinister, outlined the current violations of international law by Israel against Palestine. It warned that “genocide or…serious risk of genocide” threatens Gaza, and that the humanitarian situation is worsening as a consequence of an “11-week blockade on food, medical supplies” and other essentials. The document has over 800 legally qualified signatories, many of whom are lawyers and legal academics.

The letter highlighted the actions of the Israeli military on the Gaza strip and occupied Palestinian territory, as well as Israel’s new May war plan. Writers claimed that the recent offensive aims to forcibly displace Gaza’s population and “accelerate settlement development in the West Bank,” further infringing on the Palestinian people’s right to self determination. Forced displacement of communities is also prohibited under the Geneva Conventions.

The signatories reminded the UK of its joint statement, published on May 19, which expressed strong opposition to Israel’s expanded military operations in Gaza. Leaders from the UK, France and Canada acknowledged that “the level of human suffering in Gaza is intolerable” and condemned blocking humanitarian aid to civilians. The statement said that while the UK supports Israel’s “right to defend itself against terrorism,” it does not support military efforts to “expand settlements in the West Bank” or permanent forced displacement of Palestinians.

Echoing the UK’s warnings of “further concrete action” against Israel, the signatories called on the government to meet its obligations under international law and uphold the rule of law. It called on the UK to “secure an immediate, unconditional and permanent ceasefire … ensure the urgent, unconditional and unimpeded resumption of aid … lift Israel’s ban upon the United Nations Relief and Works Agency” in occupied Palestinian territory, impose sanctions on Israel, review UK-Israel trade relations, and execute International Criminal Court arrest warrants related to the conflict.