In this photo provided by Ukraine's 24th Mechanized Brigade press service, servicemen of the 24th Mechanised Brigade rest in a shelter on the front line near Chasiv Yar town, in Donetsk region, Ukraine, Thursday, Dec. 12, 2024. (Oleg Petrasiuk/Ukrainian 24th Mechanised Brigade via AP)

In this photo provided by Ukraine's 24th Mechanized Brigade press service, servicemen of the 24th Mechanised Brigade fire a 2s1 self-propelled 122mm howitzer towards Russian positions near Chasiv Yar town, in Donetsk region, Ukraine, Thursday, Dec. 12, 2024. (Oleg Petrasiuk/Ukrainian 24th Mechanised Brigade via AP)

In this photo provided by the Ukrainian Emergency Service, firefighters work on the site of a damaged building after a Russian drone attack in Kharkiv, Ukraine, early Friday, Dec. 13, 2024. (Ukrainian Emergency Service via AP Photo)