Russia and Ukraine

Russia's seizure of Ukraine ships and 24 people on the Black Sea in November caused strong protests from Kiev and deteriorated Moscow's already tense relationships with the West.

The incident led Ukraine to declare martial law and called on NATO to send ships to the area. The European Union and the United States condemned the move as the EU decided against further sanctions on Russia but extended existing ones targeting Russia's defense, energy and banking sectors, until mid-2019.

It is the most dangerous clash between the two neighbors since 2014, when Crimea held a local referendum to be incorporated into Russia. Ukraine said the peninsula was annexed.