Ukraine's decision to turn off the taps keeping Russian gas flowing via its territory to Europe has already sown trouble in the continent's east, with Moldova declaring a state of emergency and Slovakia threatening Kyiv with retaliation.

Russian gas flows through Ukraine are set to stop on Wednesday when a transit deal between the two countries expires in the wake of Moscow’s full-scale invasion. The pipeline was one of the last two routes still carrying Russian gas to Europe nearly three years into the full-scale war.

Russian gas supplies sent via Ukraine to Europe for more than 40 years are scheduled to end on January 1 after Ukraine's Naftogaz refused to renew its latest five-year transit deal with Russia's Gazprom.

MOSCOW >> Russian energy company Gazprom said it would pump a reduced volume of gas to Europe via Ukraine on Tuesday, the last day before the expiry of a deal that had kept the gas flowing throughout nearly three years of war.