UNITED NATIONS (AP) — The United States is urging other nations to tell Russia to stop making nuclear threats and end “the horror” of its war in Ukraine. All three countries’ top diplomats spoke at a high-profile U.N. Security Council meeting. But they didn’t quite meet. Held alongside the annual U.N. General Assembly gathering of world leaders, the session followed a striking development in the war this week. Russia called up a portion of its reserves for the first time since World War II. At the same time, President Vladimir Putin said his nuclear-armed country would “use all means available to us” to defend itself if its territory is threatened.