Judgment of the Court (Grand Chamber) of 4 June 2026.#AR and Procureur général de Mons v HL.#Reference for a preliminary ruling – Judicial cooperation in criminal matters – European arrest warrant – Framework Decision 2002/584/JHA – Article 1(3) – Grounds for refusal of execution – Risk of the requested person suffering inhuman or degrading treatment prohibited by Article 4 of the Charter of Fundamental Rights of the European Union – Article 4(6) – Ground for optional non-execution – Undertaking of the executing Member State to enforce the sentence in accordance with its domestic law – Framework Decision 2008/909/JHA – Mutual recognition of judgments in criminal matters – Article 4(5) – Request by the executing Member State to the issuing Member State to forward to it the judgment imposing a custodial sentence with a view to enforcing that sentence on its territory.#Joined Cases C-722/23 and C-91/24.