Poland and Romania are deploying a new weapons system to defend against Russian drones, following a spate of incursions into NATO airspace in recent months that exposed the alliance’s vulnerabilities and put Europe on edge.

The American Merops system, which is small enough to fit in the back of a midsize pickup truck, can identify drones and close in on them, using artificial intelligence to navigate when satellite and electronic communications are jammed.

As well as being deployed in Poland and Romania, Merops will also be used by Denmark, NATO military officials told The Associated Press, part of a move to boost defenses on the alliance’s eastern flank.

The aim is to make the border with Russia so well-armed that Moscow's forces will be deterred from ever contemplating crossing, from Norway in the north to Turkey in the south, the officials said.

The need for such technology became acute after around 20 Russian drones flew into Polish airspace in early September.

Multimillion-dollar jets were scrambled to respond to drones which cost tens of thousands of dollars.

Romania later faced a drone incursion, while drones temporarily closed airports in Copenhagen, Munich, Berlin and Brussels.

There were also sightings near military bases in Belgium and Denmark.

While the origin of the drones could not always be traced to Russia or linked to its war in Ukraine, the urgent need to bolster defenses is clear.

A protracted drone battle — or full-scale war as in Ukraine — would drain Western coffers and limited stocks of missiles.

Drones fly low and slow, making them hard to pinpoint on radar systems calibrated for spotting high-speed missiles.

They can also be mistaken for birds or planes. The Merops system, NATO officials said, helps plug those gaps.

AP production by Philipp Jenne