In response to President Biden’s announcement that he was sending advanced rocket systems to Ukraine, Kremlin spokesman Dmitry Peskov fired back Wednesday to accuse the United States of “pouring fuel on the fire.”

Russian Deputy Foreign Minister Sergei Ryabkov, meanwhile, warned on state television that deliveries of sophisticated multiple launch rocket systems to Ukraine are viewed “extremely negatively” by Moscow and could be “dangerous.”

The battle for the Donbas region continues, with Russia close to claiming full control of Severodonetsk, a city that is key to Moscow’s strategy in eastern Ukraine.

Most of the embattled city is now under Russian jurisdiction, the head of the region’s military administration said Tuesday.

Ukrainian troops appear to be withdrawing from Severodonetsk to focus on battles elsewhere, rather than fighting to the end, according to the Washington-based Institute for the Study of War.

Nearly 100 days of the conflict have left at least 5.2 million children “in need of humanitarian assistance,” UNICEF, the United Nations’ agency for children, said Wednesday.

Most of those children have been displaced by the war, which the U.N. said kills at least two children and injures at least four every day.

Russia is solely to blame for the escalation of violence in Ukraine, not the United States, Secretary of State Antony Blinken said Wednesday in response to questions about the U.S. transfer of advanced rocket systems to Kyiv.