A Ukrainian military official said Russia took the lead as fighting raged in the eastern Lugansk region.
Oleksiy Gromov, of the General Staff of the Armed Forces of Ukraine, said on Thursday that Russia had the upper hand “both in aviation and in artillery”, but that the forces in Kyiv were “trying with all their might to change the situation”.
He told a briefing in Kyiv that the situation in the Severodonetsk region was “difficult, but stable” and that Russian forces were carrying out airstrikes and artillery damage on Ukrainian troops.
“Each unit, each military is acting according to the general plan of the higher commander,” he said, according to the Interfax news agency, adding that the supply of weapons by the allies “will accelerate our victory”.
He said Russian forces were operating according to a “classic pattern” in which they first used bombers, then attack aircraft followed by attacks from artillery and ground troops.
His comments come as an adviser to Ukrainian President Volodymyr Zelensky gave a pessimistic view of the fighting in Ukraine.
Oleksiy Arestovych told the Agentsva news outlet on Wednesday that Ukrainian forces lag behind Russian forces “in terms of pace”.
He said that the Russian side had “managed to accumulate reserves before us” and that the delay in the accumulation of military resources “makes the situation at the front extremely difficult”.
He also warned that in the near future, “the situation at the front will worsen, encirclements are possible” with the prospect of abandoning colonies and “heavy losses”.
Gromov’s comments come as at least four people were killed on Thursday when the center of Kharkiv, Ukraine’s second largest city, was bombed, according to regional governor Oleh Synyehubov.
Ukraine said Russian forces attacked more than 40 towns in the eastern region of Donetsk and Luhansk, and the towns of Severodonetsk and Lysychansk were also shelled.
Ukrainian Deputy Defense Minister Hanna Maliar said on Thursday that the Russians were storming Ukrainian positions in several areas of Donbass simultaneously with “tactical rocket systems, aviation and artillery”.
“As of today, the aggressor is conducting intensified fire along the entire line of contact and positions of our forces in the Donetsk operational region,” Maliar said. Meanwhile, Russian MP and retired general Vladimir Shamanov, a retired general, suggested that the war in Ukraine is likely to be a drawn-out affair.
The RBC publication reported that he said in an interview that the “demilitarization” and “denazification” of Ukraine – the Kremlin’s justification for its invasion – could take “five to 10 years”.
Update 5/26/22, 11:00 a.m. ET: This article has been updated with additional information.