By Sabine Siebold and Ingrid Melander BRUSSELS (Reuters) -European Union leaders will hold an emergency summit on Thursday to discuss what to do next over Russia’s recognition of two breakaway regions in eastern Ukraine, after the bloc approved on Wednesday a first, limited round of sanctions. Russian President Vladimir Putin on Monday recognised the independence of two separatist enclaves in the Donbass region of eastern Ukraine that adjoin Russia, deepening Western fears of a major war in Europe. The EU sanctions set to take effect later on Wednesday include blacklisting more politicians and…