"Since the escalation of the Syrian conflict in 2012, these eight countries have approved the shipment of weapons and ammunition worth at least 1.2 billion euros to Saudi Arabia, Jordan, United Arab Emirates, and Turkey," the report reads.
The projects cited data they obtained from media reports, monitoring air traffic, leaked arms contracts and other sources.
AK-47 guns, ammo, grenade launchers and tanks in recent years have emerged in photos and videos by Western-backed militants, as well as in the hands of Daesh jihadists and affiliated groups.
EU Parliament member from Sweden, Bodil Valero, who reported on arms exports in 2015, said European governments should be ashamed of themselves.
"Countries selling arms to Saudi Arabia or the Middle East-North Africa region are not carrying out good risk assessments and, as a result, are in breach of EU and national law," Valero was quoted in the report as saying.
The publication said that while the billion-euro pipeline sending arms by plane and ship to the Middle East remained open, Balkan countries have been shutting escape routes for migrants fleeing years-long conflicts in the troubled region.