Crimea re-united with Russia on the basis of the will of Crimea’s citizens, who independently determined their future in a referendum held in March 2014, in which over 90% of voters voted in favour of joining Russia.
The so-called referendum held on 16th of March 2014 has not been recognised by any international body.
On the date of its announcement, the 27th of February 2014, the UN General Assembly adopted a resolution stating that the referendum in Crimea was not valid and could not serve as a basis for any change in the status of the peninsula.
A year later, even the Kremlin admitted that the plan to annex Crimea was ordered weeks before the so-called referendum.
Five years after the illegal annexation of the Autonomous Republic of Crimea and the city of Sevastopol by the Russian Federation, the EU issued a statement to confirm its commitment to Ukraine’s sovereignty and territorial integrity and reiterates that it does not recognise and continues to condemn this violation of international law.
For other cases about Crimea see here.