The Ukrainian military and Russian-backed separatists in eastern Ukraine accused each other on January 1 of violating a shaky holiday truce between the warring sides.
Russia says it's suing Ukraine for defaulting on a $3 billion Eurobond debt owed to Moscow.
Ukraine's free-trade agreement with the European Union has come into force, coinciding with the start of Moscow's food embargo against Kyiv.
Ukrainians are debating a petition to celebrate Christmas on December 25, like Western Europe, rather than continuing to mark the holiday on January 7 according to Orthodox Christian tradition.
Ukrainian police are blaming saboteurs yet again for blowing up an electricity pylon that shut down electricity for at least one quarter of the residents of Crimea.
Crimeans are bracing for a dark, cold New Year's Eve as the peninsula is hit by yet another power outage.
A Crimean official has said that Ukraine has cut off a major source of electrical power to the region, a month after saboteurs first plunged the peninsula annexed by Russia into darkness.
Kyiv says it will approve a ban on the import of some Russian goods in response to similar actions by Moscow.
The leaders of Germany, France, Russia, and Ukraine have renewed their support for a cease-fire in eastern Ukraine during phone discussions between them.
Kyiv is threatening to take legal action over the decision by a leading winemaker in Russian-annexed Ukraine to put 13,000 vintage bottles up for auction.
German Foreign Minister Frank-Walter Steinmeier warned that the cease-fire between Ukrainian government forces and pro-Russian separatists is becoming more fragile.