Ukraine pleads for Western warplanes. Will the US help deliver?

Biden "can do more, I'm sure he can, and I would like to believe that, that he's capable of doing that," Zelenskyy told ABC News.

Ukraine President Volodymyr Zelenskyy has made repeated and passionate pleas now for the U.S. and NATO to implement a 'no-fly' zone over his country and ground Russian warplanes -- through intimidation or force.

But he's also made another ask -- one that President Joe Biden's administration said it is working with allies like Poland to facilitate -- for fighter jets to replenish the Ukrainian air force.

"We know where these Soviet planes are stationed, which countries host them, and we asked these countries," Zelenskyy told ABC News's David Muir in an exclusive interview Monday, adding Biden "can do more, I'm sure he can, and I would like to believe that, that he's capable of doing that."

U.S. officials, including Secretary of State Antony Blinken, have said the administration is working to address this, including by possibly replenishing Poland's air force with U.S. jets.