In November 2014, the Ukrainian military reported intensive movement of troops and equipment from Russia into the separatist controlled parts of eastern Ukraine. The Associated Press reported 80 unmarked military vehicles on the move in rebel-controlled areas. The Organization for Security and Co-operation in Europe (OSCE) Special Monitoring Mission observed convoys of heavy weapons and tanks in DPR-controlled territory without insignia. OSCE monitors further stated they observed vehicles transporting ammunition and soldiers' dead bodies crossing the Russian-Ukrainian border under the guise of humanitarian aid convoys. As of early August 2015, OSCE observed over 21 such vehicles marked with the Russian military code for soldiers killed in action. According to The Moscow Times, Russia has tried to intimidate and silence human rights workers discussing Russian soldiers' deaths in the conflict. OSCE repeatedly reported that its observers were denied access to the areas controlled by "combined Russian-separatist forces".

The majority of members of the international community and organizations such as Amnesty International have condemned Russia for its actions in post-revolutionary Ukraine, accusing it of breaking international law and violating Ukrainian sovereignty. Many countries implemented economic sanctions against Russia, Russian individuals or companies – to which Russia responded in kind.

In October 2015, The Washington Post reported that Russia has redeployed some of its elite units from Ukraine to Syria to support Syrian President Bashar al-Assad. In December 2015, Russian Federation President Vladimir Putin admitted that Russian military intelligence officers were operating in Ukraine, insisting though that they were not the same as regular troops. Despite being an independent country since 1991, Ukraine has been perceived as being part of its sphere of interest by Russia (Wikipedia).