Britain said it was allocating 200 million pounds ($270 million) to fund preparations for the possible deployment of troops to Ukraine, after pledging its soldiers this week to a multinational force for the country in the event of a ceasefire.

Ukrainian President Volodymyr Zelenskyy said the agreements were “a signal of how seriously Europe and the entire coalition of the willing are ready to work for real security.”

People will be more willing to return if Ukraine is able to regain most of the territory seized by Russia since 2014, Hladun suggests. But anything short of that could leave Ukrainians feeling vulnerable as it would be considered a temporary ceasefire rather than a complete end of hostilities.

NATO allies in the Coalition of the Willing are planning security guarantees for Ukraine once Russia's war is over.

Russia's overnight attack on Ukraine's energy infrastructure leaves nearly 800,000 homes without power amid freezing winter temperatures across the country.