EU leaders will gather in Copenhagen on Wednesday for informal talks centered on defense and Russia's war in Ukraine, following recent airspace incursions and drone sightings that have heightened security concerns.

Discussions are expected to focus on strengthening the EU's shared defense capacities, supporting Eastern European countries bordering Russia and providing further aid to war-torn Ukraine.

The previously planned gathering comes after the Danish government called repeated drone sightings that heavily disrupted Danish air traffic a "hybrid attack."

Earlier in September, three Russian fighter jets entered Estonian airspace after a large number of Russian drones penetrated Polish airspace.

European Council President Antonio Costa, in an invitation letter to EU leaders, described the incidents as "a stark reminder that we must accelerate and deepen our efforts."