Does Crimea now constitute a part of Russia or Ukraine? De facto, the answer is undoubtedly Russia. As early as March 2014, Secretary of State John Kerry conceded that Russia had "complete operational control of the Crimean peninsula." De jure, the answer is more complicated. Ukraine contends that Russia unlawfully "annexed" Crimea, while Russia contends that Crimea lawfully declared independence and "acceded" to Russia.
Sovereignty over Crimea: A Case for State-to-State Investment Arbitration,
Yale J. Int'l L.
Available at: https://digitalcommons.law.yale.edu/yjil/vol41/iss2/5