Fighting is intensifying in Ukraine's east and some other regions, as Friday marks one year since the Russian invasion began.
The founder of Russian private military company Wagner Group claims that it had taken control of a village on the outskirts of Bakhmut, a key stronghold of Ukrainian forces in the eastern region of Donetsk.
Ukrainian President Volodymyr Zelenskyy on Friday spoke at a ceremony in Kyiv, addressing soldiers who are fighting against Russian forces.
He hailed all the soldiers and volunteers who are defending Ukraine as the country's heroes, and said they are working hard for victory. He called on soldiers and citizens to continue to unite and stand against Russia.
Meanwhile, Russia's defense ministry said on Thursday that Ukraine is planning to invade Moldova's eastern region of Transdniestria. The pro-Russia breakaway region has unilaterally declared independence and has been hosting Russian forces.
The ministry said Russian forces will adequately respond to what it called a provocation by the Ukrainian side.
Earlier, the defense ministry said Ukraine planned to stage a false-flag operation by purported Russian forces from Transdniestria, but offered no evidence.
The Moldovan government declined to confirm the Russian defense ministry's allegations.
Ukrainian presidential adviser Mykhailo Podolyak criticized Russia for attempting to destabilize Moldova's political situation.
Moldovan President Maia Sandu criticized Russia on February 13, saying she received information that Moscow was plotting to use saboteurs to topple her government.
Moldova is on heightened alert against possible Russian intervention.