At least one person has been killed after Russia launched its largest drone attack on Ukraine since the beginning of its invasion, Ukrainian officials said Wednesday, just hours after US President Donald Trump pledged more military support for Kyiv and accused his Russian counterpart Vladimir Putin of throwing “bullsh*t” over peace talks.

The Russian leader is convinced that Moscow’s battlefield superiority is growing, and that Ukraine’s defenses may collapse in the coming months, according to people close to the Kremlin.

Trump’s decision to help Ukraine fight an onslaught of Russian attacks reverses a Pentagon decision to withhold defensive weapons.