WASHINGTON, March 10 - The Pentagon is exploring ways to shore up Ukraine’s air defenses by facilitating the transfer of Soviet-designed antiaircraft equipment, according to U.S. and European officials, The Wall Street Journal reported.

The U.S. is trying to determine which type of air-defense systems would work best, with Soviet-designed systems—ideally mobile ones—being the best option because they would require less training for the Ukrainians, a Pentagon official said.

Russia has escalated its attacks on Ukrainian cities, and the government in Kyiv has pressed the West to provide more military assistance, including combat planes. The Pentagon on Wednesday closed the door on the transfer of Polish MiG-29s to Ukraine, but said it wants to bolster the country’s defenses, without specifying how.

“We believe the best way to support Ukrainian defense is by providing them with the weapons and the systems that they most need to defeat Russian aggression. In particular, antiarmor and air defense,” Pentagon spokesman John Kirby told reporters Wednesday.

The U.S. military deemed the Polish proposal to transfer its Soviet-era aircraft as “high risk” and assessed that it wouldn’t “significantly change the effectiveness of the Ukrainian Air Force relative to Russian capabilities,” Mr. Kirby said.

The U.S. is looking at transferring air-defense systems from former Eastern Bloc
countries that are North Atlantic Treaty Organization members, the Pentagon official said, and could be more useful than new planes in the effort to prevent Russian warplanes from flying over Ukraine.

The surface-to-air systems under consideration are more sophisticated than the shoulder-launched, heat-seeking missiles NATO members and others have already provided Ukraine. They include what NATO refers to as the SA-8 and SA-10, which can target planes at much higher altitudes, as well as what Russia calls the S-300, which was a state-of-the-art system until a few years ago.

The S-300 is an air-defense system, first produced by the Soviet Union and later Russia, that is capable of shooting down aircraft and cruise missiles. The S-300 was designed to be highly mobile, allowing air-defense forces to fire their weapons and quickly relocate to avoid being hit in a retaliatory strike.

Ukraine has some S-300s in its inventory, which have been used during the war against Russian warplanes and inbound missiles.

Western officials haven’t said where they would acquire the S-300s for Ukraine, but three NATO countries—Bulgaria, Greece and Slovakia—have the systems in their inventories.

A European diplomat said that Soviet-made systems like the S-300 would be easiest for the Ukrainians to integrate into their arsenal and employ quickly and effectively. The European diplomat suggested that the countries closest to Ukraine geographically that possess such systems could provide theirs to Kyiv on the understanding that other allies would replenish the countries’ stores with comparable systems. (wsj/ez)