The halt of Russian gas transit to Europe via Ukraine will have a "drastic" effect on the European Union, Slovak Prime Minister Robert Fico warned on Wednesday, despite the European Commission saying that the bloc had prepared for the cut-off.
"Halting gas transit via Ukraine will have a drastic impact on us all in the EU but not on the Russian Federation," Fico said on Facebook.
Russian gas exports via Soviet-era pipelines running through Ukraine came to a halt on New Year's Day, marking the end of decades of Moscow's dominance over Europe's energy markets.
The gas had kept flowing despite nearly three years of war, but Russia's gas firm Gazprom said it had stopped at 5 a.m. GMT after Ukraine refused to renew a transit agreement.
The last remaining EU buyers of Russian gas via Ukraine, such as Slovakia and Austria, have arranged alternative supply, while Hungary will keep receiving Russian gas via the TurkStream pipeline under the Black Sea.
But Transdniestria, a breakaway pro-Russian region of Ukraine's neighbor Moldova also reliant on the transit flows, cut off heating and hot water supplies to households early on Wednesday. Local energy company Tirasteploenergo urged residents to dress warmly, hang blankets or thick curtains over windows and balcony doors, and use electric heaters.
The European Commission said the EU had prepared for the cut-off.
"The European gas infrastructure is flexible enough to provide gas of non-Russian origin," a spokesperson for the commission said. "It has been reinforced with significant new LNG (liquefied natural gas) import capacities since 2022."
Russia and the former Soviet Union spent half a century building up a major share of the European gas market, which at its peak stood at around 35%. But the EU has slashed its dependence on Russian energy since the start of the war in Ukraine by buying more piped gas from Norway and LNG from Qatar and the United States.
Ukraine, which refused to extend the transit deal, said Europe had already made the decision to abandon Russian gas.
Ukraine will lose up to $1 billion a year in transit fees from Russia. To help offset the impact, it will quadruple gas transmission tariffs for domestic consumers from Wednesday, which could cost the country's industry more than 1.6 billion hryvnias ($38.2 million) a year.
Gazprom will lose close to $5 billion in gas sales.
The company halted supply to Austria's OMV in mid-November over a contractual dispute but in recent weeks Russian gas has been reaching Austria via Slovakia at a rate of around 200 gigawatt hours (GWh) per day.
For Jan. 1, only about 7 GWh per day is expected to flow from Slovakia to Austria, Austrian energy regulator E-Control said.
Slovakia's main gas buyer SPP said it would supply its customers mainly via pipelines from Germany and also Hungary, but would face additional transit costs.
Combined pipeline routes from Russia delivered a record high 201 billion cubic meters (bcm) of gas to Europe in 2018.
The Nord Stream route across the Baltic Sea to Germany was blown up in 2022 and the Yamal-Europe pipeline via Belarus has also shut.
Russia shipped about 15 bcm of gas via Ukraine in 2023, down from 65 bcm when the last five-year contract began in 2020.
