Austria’s leader met Monday with Russian President Vladimir Putin, warning after his visit to Moscow that Russia is set to intensify the brutality of its assault on Ukraine. Chancellor Karl Nehammer said he spoke with Putin for about 75 minutes, becoming the first European leader to meet with Putin since Russia invaded Ukraine in late February. This comes as Ukraine’s government says tens of thousands of Russian troops are massing for a major new offensive in eastern Ukraine aimed at capturing the entire Donbas region. On Monday, Ukrainian President Volodymyr Zelensky addressed South Korea’s parliament, asking for military aid. Zelensky also said the death toll in the besieged city of Mariupol was far higher than previously reported.

President Volodymyr Zelensky: “Mariupol has been destroyed. There are tens of thousands dead. But even despite this, the Russians are not stopping the offensive operation. They want to make Mariupol a demonstratively destroyed city.”

Zelensky’s claims could not be confirmed, as Mariupol remains largely cut off from the outside world. On Monday, Mariupol’s mayor told reporters more than 10,000 civilians have died in the city. Meanwhile, the Pentagon says it’s monitoring unconfirmed reports that Russian troops used chemical weapons during the assault on Mariupol.