Slovakia will consider reciprocal measures against Ukraine such as halting back-up electricity supplies after Jan. 1 if Kyiv, as expected, stops the transit of Russian gas to Slovakia, Prime Minister Robert Fico said on Friday.

Slovak Prime Minister Robert Fico announced on Dec. 27 that his government will evaluate potential reciprocal measures against Ukraine, including halting electricity supplies, if Ukraine stops the transit of Russian gas to Slovakia after January 1.

Benchmark European natural gas futures jumped as much as 5% in early trading Friday after Russia's President Putin said it would be impossible to reach agreement on any new transit contract for the flow of natural gas through Ukraine to Europe before year’s end.

Ukrainian President Volodymyr Zelenskiy on Monday blasted Slovak Prime Minister Robert Fico over his reluctance to end his country's dependency on Russian gas, calling it a "big security issue" for Europe and saying Fico declined compensation.