Russian President Vladimir Putin has visited the headquarters of what he calls the "special military operation in Ukraine." The move suggests he will continue Moscow's invasion of the country.

Russia's presidential spokesperson announced on Saturday that Putin visited the headquarters the day before. The spokesperson said Putin gave a pep talk to military commanders, including defense minister Sergei Shoigu and Chief of General Staff Valery Gerasimov.

Putin said he wanted to hear their proposals on the immediate and medium-term actions of Russian forces.

The presidential office has denied possibilities of a ceasefire during the Christmas and New Year holidays.

Russia's massive missile attacks knocked out power in Ukraine's capital Kyiv and other regions across eastern and southern Ukraine on Friday.

Ukraine said it shot down 60 of 76 Russian missiles, including cruise missiles, that targeted critical infrastructure.

Ukraine's Energy Minister Herman Halushchenko said at least nine power-generating facilities had been hit and the power supply was down to 50 percent.

Ukrainian President Volodymyr Zelenskyy said Russia still has enough missiles for several more massive strikes. But he added that Ukraine has the determination and self-belief to fight back.

US think tank The Institute for the Study of War said Russia carried out one of the largest missile attacks on Kyiv to date. It said Russian forces are probably intensifying their strikes on Kyiv "to stir up societal discontent in the capital." But it also said the missile attacks are unlikely to break Ukraine's will.