Senior Conservative politicians have written to England's chief prosecutor, asking if the trial of two men accused of spying for China could be resumed if the Government formally designates Beijing a national security threat. The original case against Christopher Cash and Christopher Berry collapsed after the Government failed to provide evidence that China posed such a threat, leading to dropped charges. The issue has sparked political blame, with Conservatives and Labour exchanging accusations over who is responsible for the failure to prosecute, and whether economic ties with China influenced the decision. Downing Street has denied any political interference in the case, insisting the decision was made independently by prosecutors.