Military aid to Ukraine shifts toward defence industry and unmanned naval systems

"Defence procurement is not a one-way street. Looking at drones, there is certainly a lot that we might want to buy from Ukraine, though, for now, I believe they need their entire output themselves," Keller said.

NATO's Deputy Supreme Allied Commander Europe, Admiral Keith Blount, also says Western allies may learn a lot from Ukraine, in particular on autonomous weapons such as drones.

"We're learning about power of autonomy in a way that we always imagined was the future, but we are seeing it accelerated perhaps even faster than any of us could have imagined", Blount told Reuters while visiting NSATU's headquarters.

He was referring to the use of drones on the sea, beneath the sea and on the ground as well as in the air.

"That has been logarithmic, really, in the pace of adoption and actually the ability for Ukraine not just to learn how to use them, but learn how to make them, which has been fascinating," he said.