The influential International Relations Committee of the United Kingdom’s House of Lords issued a highly critical report this week on UK policy towards the Middle East. Whoever forms the next UK government should look closely at the report’s recommendations, especially on arms sales to the Gulf.

While noting the commercial benefits, the report says sales can “cut across our wider interests in stability, our humanitarian responsibilities, and our obligations under international law,” and suggests those conflicts of interest “have become glaring in the case of the war waged in Yemen.”

Human Rights Watch shares these concerns. We have closely investigated the conduct of the warring parties there, including the Houthi-Saleh forces and the Saudi-led coalition, and we’ve exposed multiple violations of the laws of war. Given the UK’s huge diplomatic and military support to the Saudis, it has been particularly important to monitor their conduct.

To date, we have identified 81 attacks by the Saudi-led coalition that appear to have violated the laws of war, some likely amounting to war crimes. This includes attacks on homes, schools, clinics, markets and mosques. The United Nations and Amnesty International have also identified dozens of apparently unlawful coalition strikes.

At least 4,773 civilians have been killed and 8,272 wounded since the start of the conflict in March 2015, with coalition airstrikes responsible for the majority of those civilian casualties.

But despite this overwhelming evidence, the UK government still won’t acknowledge that the Saudi-led coalition – which the UK supports and arms – has committed any violations. Initially, UK ministers suggested that the Ministry of Defence was assessing allegations of unlawful strikes, and that this process confirmed Saudi compliance with the laws of war. Last summer, however, ministers dramatically revised their position, acknowledged that some previous parliamentary statements were false, and said the UK is not able to reach a view on Saudi compliance. Yet, bizarrely and illogically, the UK government is contesting through the courts a challenge to the legality of its policy on arms exports to Saudi Arabia, as if the lawfulness of previous Saudi strikes in Yemen is irrelevant to current and future UK policy.

However the court rules, business as usual is clearly not a tenable position for the next UK government. As the Lords report recommends, there should be a major review of UK policy on arms exports, and future policy should demonstrate “unequivocal adherence to international law.”

All UK political parties ought to be able to sign up to that.