For the first time, the Ukrainian military has said that Russian forces have begun to blow up bridges to slow a Ukrainian counter-offensive in the north-east.
In its latest operational update, the General Staff said Saturday that in the area of Tsyrkuny and Rusky Tyshky east of Kharkiv, "the occupiers blew up three road bridges in order to slow down the counter-offensive actions of the Defense Forces."
CNN cannot independently verify the claim.
In the past two weeks, Ukrainian troops have retaken a number of villages to the north and east of Kharkiv, making it more difficult for Russians to use artillery against the city as well as threatening to interdict Russian supply lines for forces fighting in Donetsk and Luhansk.
Kharkiv is close to the Russian border, and was one of the first cities to come under attack when Russia invaded.
Lull in Russian offensive: The General Staff said for the second consecutive day that there had been few offensive actions by Russian forces, but that artillery fire and aerial reconnaissance continued.
Some Ukrainian officials believe Russian units are pausing before launching the next phase aimed at securing all of Donetsk and Luhansk.
Beyond these two regions, the General Staff says, the Russians have continued to shell the southern city of Mykolaiv. To the north of the city, Ukrainians claimed to have destroyed "a warehouse with ammunition and up to 20 units of enemy military equipment."
Russia's "Victory Day": Tensions are rising ahead of May 9, known as Russia's "Victory Day" -- marking Moscow's victory over Nazi Germany. Western officials have warned that Russian President Vladimir Putin could formally declare war on that day, allowing him to mobilize reserves and ramp up the Russian assault.
In the lead-up to the day, Russian forces occupying the Ukrainian region of Kherson have increased checkpoints and patrols, said the Ukrainian General Staff.
The Russian-appointed deputy head of the Kherson military administration, Kirill Stremousov, said on Friday that residents would be allowed to have Russian passports. Also on Friday, a senior Russian official was in the region with the leader of the self-styled Donetsk People's Republic.