The former head of the U.S. Army in Europe told CBS Sunday that the Biden administration's new commitment of $800 million in aid to Ukraine would" still not be enough" to help it win the war against Russia.

Appearing Sunday on CBS's "Face the Nation," Ret. Lt. Gen. Ben Hodges told host Margaret Brennan that what Ukraine has, and is receiving right now, "would still not be enough.

"What the Ukrainians need desperately are long-range fires, rockets, artillery, and drones, that can disrupt or destroy the systems that are causing so much damage in the Ukrainian cities, and which also play a critical role in this next phase, if and when it begins."

Earlier, Hodges mentioned that "phase 2" was currently underway and that he didn't believe there would be a phase 3. Instead, the retired general said the fighting will likely continue in Ukraine's eastern Donbas region but that Russia didn't have the capability to keep fighting.

"Interestingly," Hodges says, the General Staff of the Armed Forces of the Russian Federation "has decided not to mobilize all of their reservists, which tells me there is not going to be a phase 3. What we're going to do now for the next few weeks is phase 2, and they're going to focus on trying to gain control of all of Donbas. And I think that is going to be it for the rest of the year because they don't have the capability, I don't believe — especially if they don't mobilize reserves — to continue the fight after this."

Hodges points out this doesn't mean the end of the war; instead, he believes Russia will concentrate their fighting in the Donbas region rather than expanding further into Ukraine.

But also on Sunday, Ukrainian President Volodymyr Zelenskyy told CNN's Jake Tapper that Ukraine should prepare for the possibility of a nuclear attack.

"We shouldn't wait for the moment when Russia decides to use nuclear weapons​.​ … We must prepare for that​," Zelenskyy recently said, according to a report from The Hill.

"Anti-radiation medicine and air raid shelters would be needed" and notes Russia could "use any weapon, I'm convinced of it​.​"

On Thursday, CIA Director William Burns said that the U.S. cannot "take lightly" the possibility of Russia using tactical nuclear weapons as it grows more desperate in its military attack on Ukraine.

"Given the potential desperation of [Russian] President [Vladimir] Putin and the Russian leadership, given the setbacks that they've faced so far militarily, none of us can take lightly the threat posed by a potential resort to tactical nuclear weapons or low-yield nuclear weapons," Burns stated.

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