Ukrainian Foreign Minister Andriy Sybiha called another attack by the Russian Federation on the Ukrainian energy system - Putin's response to those who spoke about an illusory "Christmas ceasefire."

"Ukraine was brutally attacked on Christmas Day," said Keith Kellogg, President-elect Donald Trump's pick for Ukraine and Russia envoy.

Moscow again struck Ukraine’s energy infrastructure, part of an effort to wear down the country. “In the trenches, there are no holidays,” one man said.