WARSAW — German Defense Minister Boris Pistorius expressed skepticism about the concept of a “drone wall” to protect eastern countries against Russian aerial incursions — a project currently being pushed hard by the European Commission.

“I very much appreciate the idea of a drone wall, but we should pay attention to manage expectations. We are not talking about a concept that will be realized in the next three or four years,” he said at a panel at the Warsaw Security Forum that included EU Defense Commissioner Andrius Kubilius.

“We have to think and act in priorities and there are others, I think. We need more capabilities and more capacities,” the German minister added.

“Drone defense, of course, but not by a drone wall,” he stressed, adding that the priority is to make sure that development and procurement processes are flexible enough because of how fast the technology is evolving.

His comments come as drones violated Polish, Romanian, Danish and Norwegian airspace in the past weeks; Russian fighter jets also crossed into Estonian airspace before being chased off. That’s increasing pressure on NATO and the EU to respond.

Last week, Kubilius hosted a meeting with eastern flank countries, including Bulgaria, Estonia, Finland, Latvia, Lithuania, Poland, Romania, Hungary and Slovakia to discuss a drone wall.

He has previously said that such a project could be ready in a year; the Commission is working on the scheme’s technical and financial details.

The drone wall plan will be on the agenda of Wednesday’s informal meeting of European leaders in Copenhagen.

Invest faster

Despite that worry about over-committing to a drone wall, EU and NATO countries should swiftly develop and purchase counter-drone technology, Dutch Defense Minister Ruben Brekelmans said, speaking on the same panel.

“We should all invest in more effective counter-drone systems [to protect] the entire eastern flank,” he told the audience. “We need to cooperate with Ukraine and be much quicker than we are right now.”

“We talk about months and even years: we don’t have time because drone incursions are already here,” the Dutch minister stressed, adding that shooting down cheap Russian drones with expensive fighter jets is not efficient. Dutch F-35s were involved in downing Russian unmanned aerial vehicles in the Polish airspace earlier this month.

He was echoed by Kubilius, as well as other national defense ministers present in Warsaw, and Ukrainian President Volodymyr Zelenskyy.

Ukraine is keen to help build a joint air defense shield, Zelenskyy told the Warsaw Security Forum earlier on Monday, addressing the conference by video link. “The response must be joint, fast and leave no opportunities unused. We are ready to share our know-how and our expertise,” he said.

Many of the speakers pointed out that Ukraine has built up formidable air defenses manned by experienced troops and is engaged in a technological arms race with Russia, giving it crucial advantages over European militaries.

However, it won’t be easy for Europe to replicate those same capabilities without being under the same level of threat as Ukraine.

Hanno Pevkur, Estonia’s defense minister, warned that despite its massive efforts, Ukraine “cannot take down everything,” adding that if Europe moves in the same direction, countries could end up spending 10 percent of defense budgets on standby capabilities at a time when there is no state of war with Russia.

Both Kubilius and Pistorius also said that Russia’s “provocations” are increasing. “Russia is becoming more and more of a threat to NATO,” Pistorius stressed.

He was echoed by Zelenskyy’s stark warning: “Russia is testing to see how far it can go.”

Jan Cienski contributed reporting.