Apparently the Biden administration is busy working on just that, also at a moment Congress is still prepping a whopping $10 billion military and humanitarian aide package for Ukraine. The new aircraft deal would involve transferring Russian-made warplanes to Kiev from neighboring Poland, according to a new report in FT. 

To expedite the deal - given the battlefield situation and Ukraine's ability to defend itself depends largely on the speediness of getting sufficient arms - Washington would quickly replace Warsaw's MiG-29 jets with F-16 fighters.

However, a White House official was quoted in the FT report as admitting the deal could be held up by "a number of challenging practical questions, including how the planes could actually be transferred from Poland to Ukraine."

Further there's the question of recent threat's by Vladimir Putin himself against any country seeking to pour more weapons into the hands of the Ukrainian forces. Putin days ago issued a veiled threat of war against any country supplying weapons that are use to kill Russian soldiers, saying those outside nations would "bear the responsibility". 

A White House spokesperson had confirmed to FT that "We are also working on the capabilities we could provide to backfill Poland if it decided to transfer planes to Ukraine." And previously Secretary of State Antony Blinken said the US is "very actively" looking at resupplying Poland if it can quickly transfer its own Russian-made aircraft to Ukraine. 

"We are looking actively now at the question of airplanes that Poland may provide to Ukraine and looking at how we might be able to backfill should Poland decide to supply those planes," Blinken said in Moldova, while on a trip that highlighted the growing refugee crisis from the war.