Ukrainian servicemen of the State Border Guard Service wait for an order to move to the mortar position at the entrance of the shelter in Bakhmut on February 16, 2023, as the head of Russia's mercenary outfit Wagner said it could take months to capture the embattled Ukraine city and slammed Moscow's “monstrous bureaucracy” for slowing military gains. (Photo by Yasuyoshi Chiba/AFP Photo)

A Ukrainian service member smokes near a frontline, amid Russia's attack on Ukraine, in Donetsk region, Ukraine on February 8, 2023. (Photo by Yevhenii Zavhorodnii/Reuters)

A Ukrainian serviceman smokes a cigarette at his position at the frontline near Bakhmut, Donetsk region, Ukraine, Wednesday, January 11, 2023. (Photo by Evgeniy Maloletka/AP Photo)

A serviceman of the Carpathian Sich Battalion is seen at his position on a frontline, as Russia's attack on Ukraine continues, near the town of Lyman, Donetsk region, Ukraine on December 8, 2022. (Photo by Viacheslav Ratynskyi/Reuters)

A Ukrainian gunner sits in his 2S1 Gvozdika (122-mm self-propelled howitzer) on the front line in Southern Ukraine on October 8, 2022, amid the Russian invasion of Ukraine. (Photo by Dimitar Dilkoff/AFP Photo)

Ukrainian serviceman Valerii looks on at a position in a frontline, amid Russia's attack on Ukraine, in Mykolaiv region, Ukraine on October 26, 2022. (Photo by Valentyn Ogirenko/Reuters)

A Ukrainian service member shoots from a machine gun at a position on the front line, amid Russia's attack on Ukraine, near the town of New York, Donetsk region, Ukraine on June 9, 2022. (Photo by Gleb Garanich/Reuters)

Ukrainian platoon commander Mariia talks on the phone in a position in the Donetsk region, Ukraine, Saturday, July 2, 2022. Ukrainian soldiers returning from the frontlines in eastern Ukraine’s Donbas region describe life during what has turned into a grueling war of attrition as apocalyptic. Mariia, 41, said that front-line conditions may vary depending on where a unit is positioned and how well supplied they are. (Photo by Efrem Lukatsky/AP Photo)