The British government faces possible legal action over exports of riot control equipment to US authorities amid concerns about police brutality following a wave of protests sparked by George Floyd’s death. Lawyers have sent a pre-action protocol letter, the first step in a potential high court challenge, to the international trade secretary, Liz Truss, in an attempt to stop sales of equipment including CS gas, teargas and rubber bullets. The letter, sent on Tuesday, asks Truss to confirm whether a decision has been made over the suspension of licences that allow firms to export such equipment to the US and, if not, to urgently suspend all licences. It also sets out potential grounds for a legal challenge if the government refuses to suspend export licences, stating that lawyers will argue such a decision would be unlawful. The action is being brought by a black British citizen, who does not wish to be identified at this stage. The proposed claimant attended university in the US and has friends there who have allegedly been attacked by police during protests. The letter, sent by law firm Deighton Pierce Glynn, reads: “Following the death of George Floyd and the widespread protests that immediately followed and currently continue across all states, the claimant has become increasingly concerned over the excessive militarised police response to the protesters. “The claimant has received a number of harrowing accounts from her friends who have been attempting to exercise their rights to peacefully protest. “The claimant is extremely concerned by reports that the UK Government is currently permitting the supply and export of equipment to the USA in circumstances where there is a real risk that such UK-manufactured military and law-enforcement equipment is being used against protesters in dangerous and highly inappropriate repressive ways.” US police have faced criticism for the way they have dealt with the unrest, using batons, teargas and shields against unarmed civilians. The protests erupted following Floyd’s death in police custody, after an officer refused to lift his knee from Floyd’s neck – despite his protests that he could not breathe. The threatened legal challenge is the latest call for the government to address the issue of export licences. The shadow international trade secretary, Emily Thornberry, wrote to Truss on 2 June to request the suspension of exports of riot control equipment to the US, pending a review of whether they are being used in response to the Black Lives Matter protests in American cities. On 5 June, a cross-party group of 166 MPs wrote to Truss calling for an immediate end to exports including teargas and rubber bullets to the US while an investigation takes place. Addressing those developments, the latest letter noted that Thornberry’s request has received no response. It continues: “In the current circumstances, the defendant’s silence is concerning. Action is required now to ensure that no exports are made to the US in the context where weapons such as teargas are being used against protesters and journalists. Thus, our client requires urgent clarification of what the defendant’s position is.” The letter points out the UK announced in June last year that it was suspending future sales of teargas and other crowd control equipment to Hong Kong pending an investigation into allegations of police brutality during mass protests there. The proposed claimant said in a statement: “I’m outraged that the UK is playing any role in arming the US police departments as they forcefully repress their people and disregard the humanity of black people in a show of flagrant racism.” They added that their friends in the US “are having to use their right to protest as the only way they can take action to highlight the racist state repression they face every day … Our government needs to break its silence, stop being complicit and take action, now.” On Wednesday the Scottish parliament voted to endorse an amendment calling on the UK government to stop the sale of crowd control equipment to the US.