In his evening address, Zelensky said the potential strike could involve drones and missiles and might be aimed at weakening Ukraine’s air defence systems. He urged residents to remain attentive to air raid alerts and follow safety instructions.

Zelensky suggested that Moscow could seek to exploit harsh winter conditions, as temperatures in several regions of Ukraine have fallen well below freezing at night.

Last week, Zelensky issued a similar warning ahead of an overnight assault. Hours later, Russian forces carried out an attack on the western city of Lviv. Russia’s military said it used its new Oreshnik medium-range missile in the strike, a claim that could not be independently verified.

The attack led to serious disruptions to electricity, water and heating in Kyiv, according to city officials. Mayor Vitali Klitschko advised some residents to temporarily leave the capital due to the pressure on essential services.

Zelensky also said talks between Ukrainian negotiators and U.S. representatives were progressing, adding that most documents were ready to be signed, without providing further details.

He said he expected upcoming international meetings, including those linked to the World Economic Forum in Davos, to support cooperation with partners and discussions on Ukraine’s reconstruction.