WASHINGTON

Ukrainian Premier Denys Shmyhal appealed directly Wednesday to US Defense Secretary Lloyd Austin for the Biden administration to provide Kyiv with American fighter jets.

Speaking alongside Austin at the Pentagon, Shymhal said Ukraine is forming a "fighter jet coalition" to bolster its military capabilities and the US would be "its most important participant" if it decides to contribute planes.

"In modern warfare, air superiority is crucial. That is why Ukraine is initiating the building of a new so-called fighter jet coalition and we are inviting the United States to become its most important participant," he said. "America can, once again, demonstrate its leadership by providing Ukraine with F-15 or F-16 aircrafts."

The comments come as Kyiv's forces prepare for an expected spring counteroffensive to roll back Russia's occupation of Ukrainian territories in the south and east.

Austin did not address Ukraine's appeal for warplanes directly but said the US "will meet Ukraine’s defense needs through this spring and beyond."

"As the president has repeatedly made clear, we will stand by Ukraine for as long as it takes," he said. "Mr. Prime Minister, Ukraine inspires the world every day with its courage and resilience. I want to thank you for your leadership and for making this trip."

In addition to F-15s and F-16s, Shymhal said Ukraine needs additional air-defense systems to defend against Russian strikes, heavy artillery, mortars and ammunition.

President Joe Biden in February ruled out providing Ukraine with US jets in the near-term, saying Washington is sending Ukrainian President Volodymyr Zelenskyy "what our seasoned military thinks he needs now."

The president has since come under bipartisan pressure to send F-16s with lawmakers sending a letter to Austin in March that said doing so "would be a significant capability that could prove to be a game changer on the battlefield.”