Russia's Defense Ministry announced a unilateral ceasefire in Ukraine during the upcoming Victory Day celebrations, which commemorate the defeat of Nazi Germany in World War II.Despite the ceasefire, Russia has warned Kyiv against trying to disrupt the festivities, threatening a massive missile response should it do so.For the first time in two decades, Moscow's Victory Day parade will proceed without military hardware, a decision driven by security concerns over potential Ukrainian drone attacks. (With inputs from agencies.)