"Ukraine is now essentially a testing ground," Reznikov told an online Atlantic Council event.
"Many weapons are now getting tested in the field in real conditions of battle against the Russian army, which has plenty of warning systems of its own.".
Kyiv is sharing details of Russian electronic warfare, signals intelligence, air defense, missile technology and more with its international partners, Reznikov said.
"We are interested in testing modern systems in the fight against the enemy, and we are inviting arms manufacturers to test new products here.".
Reznikov noted Ukraine's significant use of American, French, and Polish artillery pieces, as well as Turkish drones, among other foreign-made systems.
To finish the job, Reznikov said Ukraine needs a broad range of fresh weapons systems.
"Long-range systems would allow us to completely destroy their logistics, and rapidly cut off the Russian army from its support," Reznikov said. »