President Volodymyr Zelensky said Sunday that Ukraine will lose its war against Russia if the US Congress does not approve a major military aid package, as Russian forces heighten their pressure on a frontline city.

The Ukraine military acknowledged that the fighting around the frontline city of Chasiv Yar was “difficult” and “tense” but insisted its forces were resisting.

Amid heightened air attacks by both sides, Russia said one Ukrainian drone had hit the Zaporizhzhia nuclear plant that it has occupied since shortly after launching its invasion in 2022.

Ukraine has made increasingly urgent calls for the United States to start sending a proposed $60-billion aid package that has been blocked by Republicans in Congress for months.

“It is necessary to specifically tell Congress that if Congress does not help Ukraine, Ukraine will lose the war,” Zelensky said during a video meeting.

It would be “difficult” for Ukraine to “stay” (survive) without the aid, Zelensky added. “If Ukraine loses the war, other states will be attacked.”