There have been some big developments in the war in Ukraine, and the world's on edge wondering how it's all going to play out. So in this Squiz Shortcut, we look at Russia's big call-up of troops, its threats to go nuclear, and the way it's using referendums to claim parts of Ukraine. Squiz recommends: Global News Podcast - BBC Two Cities, Two Armies: Pivot Points in the Fight in Ukraine’s East - The New York Times