Russia is preparing for the next stage of its offensive in Ukraine, a Ukrainian military official said, after Moscow said its forces would step up military operations in "all operational areas", APA reports citing Reuters.
Russian rockets and missiles have pounded cities in strikes that Kyiv says have killed dozens in recent days.
"It is not only missile strikes from the air and sea," Vadym Skibitskyi, a spokesman for Ukrainian military intelligence, said on Saturday. "We can see shelling along the entire line of contact, along the entire front line. There is an active use of tactical aviation and attack helicopters.
"There is indeed a certain activation of the enemy along the entire front line... Clearly preparations are now underway for the next stage of the offensive.”
The Ukrainian military said Russia appeared to be regrouping units for an offensive towards Sloviansk, a symbolically important city held by Ukraine in the eastern region of Donetsk.
Ukraine says at least 40 people have been killed in Russian shelling of urban areas in the last three days, as the war launched by Russian President Vladimir Putin on Feb. 24 intensifies.