European Council President Donald Tusk urged European leaders to spend more on defense on Friday as deadly attacks in France, Tunisia and Kuwait drove home his point about dramatic changes to the security situation in Europe and its neighborhood.

Although their talks were overshadowed by the Greek debt crisis, Britain’s attempt to renegotiate its membership and a row over migration, European Union leaders also discussed at a Brussels summit how to strengthen Europe’s defense industry and how to make Europe a stronger player in the security arena.

NATO chief Jens Stoltenberg joined the 28 EU leaders to talk about “the new threats facing Europe at a time of hybrid warfare, global terrorism and cyber attacks,” Tusk said.

“Europeans must invest in their own defense to deal with a dramatically changed security environment,” he told a news conference after the summit.

Underlining his point, Islamic State claimed responsibility for a suicide bombing that killed 25 people at a mosque in Kuwait , 37 people were killed in a shooting at a Tunisian hotel, and a decapitated body was found after an explosion in France.

Image: President of the EU Council Donald Tusk, June 25, 2015 (photo: EU Council)