Ukrainian President Volodymyr Zelensky delivers a virtual address to Congress by video at the Capitol in Washington, on March 16, 2022 (AP)

If a no-fly zone is too much for Ukraine to ask for, President Volodymyr Zelensky told the US Congress on Wednesday, then Kiev could be given aircraft and S-300 air defense systems.

"Is this a lot to ask for to create a no-fly zone over Ukraine to save people? If this is too much to ask, we offer an alternative. You know what kind of defense systems we need - S-300 and other similar systems," he told the US legislative body.

He also stressed that the Americans know how much the battlefield depends on the ability to have access to the airspace. "Powerful strong aviation to protect our people, our freedom, our land, aircraft that can help Ukraine, help Europe," he claimed during a videoconference with Congress.

Zelensky noted that Washington knew the equipment existed, "But they are on the ground, not in the Ukrainian sky."

US, allies comply

The United States and its NATO allies are sending surface-to-air missile systems to Ukraine, including Soviet-era systems, such as the SA-8 and the SA-12 systems, CNN reported Wednesday, citing a senior US official.

The systems have a higher engagement altitude than the Stinger shoulder-held missiles the US had sent Kiev.

The systems are "on the way" to Ukraine, the official added.

However, despite Washington revealing that it was delivering SA systems, a US representative told CNN now had S-300 defense systems in the country.

"I'm pleased to say that [Ukraine] do have S-300s in the country now," Rep. Michael McCaul told the US media outlet.

Kiev had made an admission that establishing a no-fly zone over Ukraine as Russia's special military operation in the country continues could potentially lead to a direct war between the Russian Federation and NATO, according to Andriy Yermak, head of Volodymyr Zelensky's office. However, it was still reiterating the plea for the action.

Ukraine has long been asking NATO and the United States to impose a no-fly zone in its airspace, but Brussels and Washington have dismissed the requests.

White House spokesperson Jen Psaki said last week that the United States is not interested in the establishment of a no-fly zone over Ukraine since it would require the military to shoot down Russian airplanes, which would lead to a war with Russia.

US defense secretary Lloyd Austin underlined that establishing a no-fly zone over Ukraine could lead the United States into a direct war with Russia.