Hard turn-downs are hard turn-downs. He can’t turn a sow’s ear into a silk purse.
He’s too much of a wuss to just say that Ukraine should be in NATO since 69% of them want that.
Wikipedia:
Some 69% of Ukrainians want to join NATO, according to a June 2017 poll by the Democratic Initiatives Foundation
https://en.wikipedia.org/wiki/Ukraine%E2%80%93NATO_relations
If Biden had balls he’d say we’re gonna fast-track that NATO application.
But does NATO want Ukraine as a member?