Russia launched a second major drone and missile bombardment of Ukraine in four days, officials said Tuesday, aiming again at the power grid and apparently snubbing U.S.-led peace efforts as the war approaches the four-year mark.

In total, Russia fired at least 293 drones and 18 missiles overnight, according to the Ukrainian air force. Those figures surpass the attack last Thursday night into Friday, when a total of 278 aerial weapons were deployed, including an Oreshnik hypersonic ballistic missile.

Russia struck cities across Ukraine with missiles and drones overnight in one of its biggest attacks of the New Year so far, killing at least four ​people and knocking out heat and power, exposing millions to dangerous winter cold.

Moscow said the overnight strike was in response to an alleged Ukrainian drone strike on a residence used by President Vladimir Putin, which the U.S. and others said did not happen.

Russia said Friday it used its latest missile against Ukraine for a second time in the nearly 4-year-old war, a forceful signal to Kyiv and its Western allies as U.S.-led peace talks have entered a new and crucial stage.

Russia fired a hypersonic Oreshnik missile at Ukraine in retaliation for an alleged attack on one of Putin's residences that the U.S. and Ukraine have denied.