Ukraine faces "grave consequences" from Russia for its decision to sign a trade agreement with the European Union, the deputy foreign ministry has warned.
Grigory Karasin's comments after Ukraine's president Petro Poroshenko agreed a three-year deal with the EU.
Kremlin spokesman Dmitry Peskov said Russia would take measures to protect its economy if it was negatively affected by Ukraine, Georgia and Moldova's agreements.
More top news
A look ahead to the forecast for today across the UK.
People have been warned to prepare for cold weather as ice and snow is set to hit parts of the UK.
There is concern that the lack of clean water could add mean more people fall victim to the worst recorded cholera outbreak in history.