Russian-backed rebels in Ukraine's east vow they will "intensify" their fight against Ukrainian troops.
According to Kyiv, more than 180 children have been murdered since Russia launched its assault on February 24.
In Moscow, Austrian Chancellor Karl Nehammer will meet with Russian President Vladimir Putin.
According to a local official, the death toll from the Kramatorsk train station incident has risen to 57.
There are "huge signs" of war crimes in Ukraine, according to Germany's foreign minister.