Live updates Russias war in Ukraine

Live updates: Russia’s war in Ukraine

A Ukrainian Air Force Mig-29 takes off from Mykolaiv Air Force Base on a training mission to Ukraine in 2016.  Ukrainian President Volodymyr Zelenskyy has repeatedly asked other countries for Soviet-era Mig-29 Fulcrum fighter jets, which Ukrainian pilots are already able to fly. A Ukrainian Air Force Mig-29 takes off from Mykolaiv Air Force Base on a training mission to Ukraine in 2016. Ukrainian President Volodymyr Zelenskyy has repeatedly asked other countries for Soviet-era Mig-29 Fulcrum fighter jets, which Ukrainian pilots are already able to fly. (Giovanni Colla/Stocktrek Images/AP/FILE PHOTO)

The Ukrainian Air Force has added about 20 more operational aircraft to its fleet due to an influx of spare parts, according to a senior US defense official.

Though the official declined to specify which country supplied the plane parts, the official said Wednesday that the U.S. and other countries are working to “get them the parts they need to get them airborne.”

The flow of spare parts has allowed Ukraine to expand its fleet of operational military aircraft despite the ongoing Russian invasion. They have more planes now than they did three weeks ago, the official said.

A day earlier, Pentagon spokesman John Kirby said Ukraine had received additional fighter jets to increase its existing numbers.

But on Wednesday, the senior defense official echoed this, saying that Ukraine had not received more planes but had actually received plane parts to make more of its existing planes operational.

Still, the official indicated that at least one country is considering sending more planes to Ukraine.

“I was given to understand that an offer from another country was actually carried out,” the official said. “That offer didn’t go through, so I was ahead of the game.” It is not known which country made such an offer.

The US has pledged to send 16 Mi-17 helicopters to Ukraine, but the government has declined to participate in a transfer of Mig-29s from another country to Ukraine via the United States.

Ukrainian President Volodymyr Zelenskyy has repeatedly asked other countries for Soviet-era Mig-29 Fulcrum fighter jets, which Ukrainian pilots are already able to fly.

Zelensky has asked other Eastern European countries with fourth-generation airframes to send them to Ukraine, but no country has yet agreed.

On Wednesday, the official Ukrainian Air Force Twitter account said: “Ukraine has not received any new aircraft from partners! With support from the US government, @KpsZSU received spare parts and components for the restoration and repair of the Armed Forces aircraft fleet, allowing more equipment to become operational.”

The Ukrainian Air Force is part of its air defense network, which also includes S-300 surface-to-air missiles and man-portable anti-aircraft missiles. The combination of platforms has prevented Russia from establishing air sovereignty over Ukraine and controlling the skies.

Despite constant bombardment by Russian missiles and artillery, as well as attacks on military bases, Ukraine’s air force has remained largely intact, although it has suffered some casualties.

In early March, about two weeks into the war, the defense official said Ukraine had 56 fighter jets, accounting for about 80% of its fixed-wing fighters. But the Ukrainians didn’t use their planes much, flying only 5 to 10 missions a day, the official said.

CNN’s Ellie Kaufman contributed to this report.