European Union nations on the bloc’s eastern flank are piling pressure on Brussels to speed up the approval of air-defense funding as more military drones stray into their airspace from Russia and Ukraine, according to people familiar with the matter.

The EU has made several pools of funding available for projects that would give member states new capabilities to monitor and neutralize low-flying attack drones. Countries in the EU’s east, including Estonia and Finland, submitted projects earlier this year.